In World War 1, Chlorine gas was used as a toxic, poisonous gas to harm and terminate enemies.
A certain polyatomic ion contains 49 protons and 50 electrons. What's the net charge of this ion?A. +1B.-2C. +2D. -1
Net charge = -1. Option D is correct
Explanations:Protons are positively charged ion while electrons are negatively charged electron.
Given the following parameters
[tex]\begin{gathered} Proton\text{ number}=49protons \\ Electron\text{ number}=50electrons \end{gathered}[/tex]Determine the net charge
[tex]\begin{gathered} Net\text{ charge}=-50+49 \\ Net\text{ charge}=-1 \end{gathered}[/tex]Hence the net charge of this ion is -1
Patrick is a 16 year old boy whose body has stopped producing osteoclasts. What does this mean for his bones? What other parts of
his body will be affected by this?
Answer:
Osteoclasts are the only bone resorbing cells, so, when his body stops producing osteoclasts, it results in deficiency of bone turnover and In osteopetrotic-like diseases.The bone will be affected by this.
Match the reaction to the type that best describes it.NaF + KBr →NaBr + KF?CombinationMg + MnCl2 →Mn + MgCl2?Decomposition2HCl → H2 + Cl2?Single replacementaw2Na + O2 →Na202?Double replacement
Explanation
Let us first define the different types of reaction.
A combination reaction is one in which two reactants combine to form a single product.
[tex]2Na+O_2\rightarrow Na_2O_2[/tex]A decomposition reaction will be one in which a reactant breaks down into two or more products.
[tex]2HCl\rightarrow H_2+Cl_2[/tex]A simple displacement reaction will be one in which a reagent, which is in its natural state, displaces one element bound to another. As a product, we will have the previously linked element now in its free form.
[tex]Mg+MnCl_2\rightarrow Mn+MgCl_2[/tex]In a double displacement reaction two linked elements move past each other and take each other's place.
[tex]NaF+KBr\rightarrow NaBr+KF[/tex]9. The structural formula for pentane is shown here: Pentane can form 3 different alcohols when it gains a hydroxyl group. Write the structural formulas for these three alcohols.
Pentane has a C5H12 formula, if we take one H and substitute it with an OH (hydroxyl group), we will end up with C5H11OH, and that has a few isomers, which are different structures for the same chemical formula.
C5H11OH can be: Pentan-1-ol; Pentan-2-ol; Pentan-3-ol; Neo-pentanol; 2-methylbutan-1-ol; Iso-pentanol, and more.
Mass and energy are conservedQuestion options:A) only in chemical changes.B) in chemical changes and physical changes.C) only in physical changes.D) always in physical changes and sometimes in chemical changes.
Answer
B) in chemical changes and physical changes.
Explanation
Matter can change form through physical and chemical changes, but through any of these changes, matter is conserved. The same amount of matter exists before and after the change —none is created or destroyed. This concept is called the Law of Conservation of Mass.
Also, the law of conservation of energy states that in any physical or chemical process, energy is neither created nor destroyed. In other words, the entire energy in the universe is conserved.
Therefore, mass and energy are conserved in chemical changes and physical changes.
The correct answer is option B) in chemical changes and physical changes.
What are three characteristics of nonmetals?
Characteristics of nonmetals
1. What characterizes non-metals is that they lack the ability to conduct electricity, therefore they are poor conductors, unlike metals.
2. Non-metallic compounds in general are the basis for forming organic compounds essential for life.
3. Non-metal elements do not reflect light, are non-corrosive and are brittle, and break easily.
4. They also have high electronegativity, so when they form an ionic bond they tend to take electrons.
The Apollo 13 mission was determined to be a “successful failure”. Although the astronauts did not land on the Moon, they were successfully brought home. A thorough investigation of the explosion, based on records of manufacturing processes and maintenance logs, tracked the failure of the oxygen tank to multiple faults. None of the problems, had they occurred alone, would have been critical, but together they led to a near disaster for the crew of Apollo 13. How much carbon dioxide would have been removed from the breathing environment if the scrubber reaction produced 50.0 kilograms of lithium carbonate? Use dimensional analysis.
29,769.95g of carbon dioxide can be removed.
1st) It is necessary to write the balanced chemical reaction:
[tex]2\text{LiOH + CO}_2\text{ }\rightarrow Li_2CO_3+H_2O[/tex]According to the balanced equation, 1 mole of carbon dioxide (CO2) can be removed by producing 1 mole of lithium carbonate (Li2CO3).
Using the molar mass of carbon dioxide and lithium carbonate we can convert moles into grams:
- CO2 molar mass: 44 g/mol
- Li2CO3 molar mass: 73.9 g/mol
With the molar mass we can see that 44g of carbon dioxide (1 mole) can be removed by producing 73.9 g of lithium carbonate.
2nd) Now we can calculate the amount of carbon dioxide that can be removed from the breathing environment if the scrubber reaction produces 50.0 Kg of Li2CO3, using a mathematical rule of three:
[tex]\begin{gathered} 0.0739kgLi_2CO_3-44gCO_2 \\ 50kgLi_2CO_3-x=\frac{50kgLi_2CO_3\cdot44gCO_2}{0.0739kgLi_2CO_3} \\ x=29,769.95gCO_2 \end{gathered}[/tex]Here, it is important to convert the grams of Li2CO3 to kg before doing the calculus.
So, 29,769.95g (29.8kg) of carbon dioxide can be removed.
How are activation energy and reaction rate most likely related? (1O A faster reaction rate results in lower activation energy.A faster reaction rate results in higher activation energy.
Higher activation energy results in slower reaction rate. Option D is correct
Explanations:Activation energy is the energy required needed by compounds or molecules to undergo chemical reactions.
The activation energy of a reaction is related to the rate of reaction. They are both inversely related. In order words, as the activation energy becomes higher, the rate of reaction becomes slower.
Balance these chemical equations. (Use the lowest possible whole number coefficients.)Fe + O2 → FeO
Chemistry =>Chemical Reactions => Balancing equations
We have the oxidation of iron in the equation.
To balance the equation we must start by counting the atoms of each element on both sides of the reaction.
We will balance the oxygen. We have 2 atoms of oxygen on the reactants. So we write coefficient 2 on the FeO molecule.
[tex]Fe+O_2\rightarrow2FeO[/tex]Now, we balance the iron. We have 2 Fe atoms, so we write the coefficient 2 on the Fe molecule. We have:
[tex]2Fe+O_2\rightarrow2FeO[/tex]Now, the equation of the reaction is balanced.
Answer: 2Fe + O2 →2FeO
Find ∆°H for the reaction 2H2(g) + 2C(s) + O2(g) C2H5OH(l) using the following thermochemical equations: (4 marks) C2H5OH(l) + 2O2(g) 2CO2(g) + 2H2O(l) ∆H° = - 875 kJC(s) + O2(g) CO2(g) ∆H°= -394.51 kJH2(g) + ½ O2(g) H2O(l) ∆H° = - 285.8 kJ
Answer:
Explanation:
Here, we want to get the ∆°H for the reaction
Mathematically, to get this, we have to subtract the change in enthalpy of the reactants from that of the product
However, we shall not be considering the enthalpy values for single element molecules like hydrogen molecule and oxygen molecule
From the later reactions and values given, we can get the values for carbon (iv) oxide and Ethanol
For Carbon (iv) oxide, we have it as:
[tex]\begin{gathered} \text{ enthalpy of product - enthalpy of reactant =-394.5 KJ} \\ enthalpy\text{ of reactant here is zero} \\ \text{ Thus enthalpy of product CO}_2\text{ = -394.51 KJ} \end{gathered}[/tex]For Ethanol, we need to get the value for water
We have that as follows:
[tex]-285.8\text{ KJ}[/tex]For ethanol, that would be: Let us label it e
[tex]undefined[/tex]A formula written on the arrow in a chemical equation represents.....Group of answer choicesa reactanta producta catalystan acid
On a chemical reaction, we always have formulas on the left and right parts of the equation.
On the left, we have the reactants and on the right we have the products.
An acid is simply a type of chemical, so an acid can appear anywhere on a chemical reaction.
A catalyst is a chemical that participates on the reaction but it is not consumed. The reactants for instance, participate and are consumed.
Because catalyst are not consumed like reactants, thay need to go on another part of the equation so we don't confuse it with the other. Its place is on the arrow of the reaction.
Thus, the fomuala on the arrow is a catalyst.
Choose the diamagnetic species.
A) Ga3+
B) Cr2+
C) N
D) I
E) None of the above species are diamagnetic.
Diamagnetic species is Cr²⁺
Diamagnetic species is the species in which contain no unpaired electron
Here in the Cr²⁺ total electron in the chromium is 24 but here Cr²⁺means 2 electron are loss that's why total electron in Cr²⁺ is 22 so this is even number of electron and also no unpaired number of electron means all electron are paired that's why is called a diamagnetic and the superconductors are the perfect diamagnetic because of their ability to eject the electrons
Know more about diamagnetic species
https://brainly.com/question/15462756
#SPJ1
How many formula units make up 26.2 g of magnesium chloride (MgCl2)?Express the number of formula units numerically.
Sometimes, when working with ionic compounds like magnesium chloride we talk about formula units instead of molecules, but they are similar.
We are asked for the number of formula units (or molecules) of MgCl₂ that we have in 26.2 g of it.
Before we determine the number of formula units, we have to convert 26.2 g into moles. To do that we will use the molar mass of MgCl₂.
atomic mass of Mg = 24.31 amu
atomic mass of Cl = 35.45 amu
molar mass of MgCl₂ = 24.31 + 2 * 35.45
molar mass of MgCl₂ = 95.21 g/mol
moles of MgCl₂ = mass of MgCl₂/(molar mass of MgCl₂)
moles of MgCl₂ = 26.2 g/(95.21 g/mol)
moles of MgCl₂ = 0.275 moles
Once that we know the number of moles of MgCl₂ that we have in our sample, we can find the number of formula units. According to Avogadro's number, we have 6.022*10^23 formula units in 1 mol of formula units. We will use that conversion to get the answer to our problem.
1 mol of MgCl₂ = 6.022 *10^23 formula units
formula units of MgCl₂ = 0.275 moles of MgCl₂* 6.022 *10^23 formula units/(1 mol of MgCl₂)
formula units of MgCl₂ = 1.66 *10^23 formula units
Answer : 1.66 * 10^23 formula units make up 26.2 g of magnesium chloride.
2.(a) Draw the structural formula of octan-1-ol (C8H17OH). (b)What class of organic molecule is octan-1-ol? Explain your reasoning. (Classes of organic molecules include alkanes, alkenes, alkynes, alcohols, carboxylic acids, aldehydes, ketones, esters, ethers, amines, & amides.)(c)Define the term “isomer”.(d)Draw an isomer of octan-1-ol.
Explanations
2a) Structural formulas are defined as the way atoms and elements are arranged in a compound.
For octan-1-ol which can also be called octanol with formula C8H17OH, the structural formula is as shown below;
b) The class of organic molecules that octan-1-ol falls in is alkanol or alcohol. This is due to the presence of the -OH group present in the molecule of octan-1-ol
c) Isomers are molecules having the same molecular formula but different structural formulas. For instance, the isomer of butane is n-butane and isobutane.
d) One of the isomers of octan-1-ol is 2-methylheptanol as shown below in the image attached;
Chlorine, selenium, and bromine are
located near each other on the periodic
table. Which of these elements is (a) the
smallest atom? (b) the atom with the
highest ionization energy?
According to the electronic configuration, chlorine is the smallest atom and selenium has highest ionization energy as selenium has 4 shells and hence electrons from outermost shell cannot be easily removed thus more energy is supplied.
What is electronic configuration?Electronic configuration is defined as the distribution of electrons which are present in an atom or molecule in atomic or molecular orbitals.It describes how each electron moves independently in an orbital.
Knowledge of electronic configuration is necessary for understanding the structure of periodic table.It helps in understanding the chemical properties of elements.
Elements undergo chemical reactions in order to achieve stability. Main group elements obey the octet rule in their electronic configuration while the transition elements follow the 18 electron rule. Noble elements have valence shell complete in ground state and hence are said to be stable.
Learn more about electronic configuration,here:
https://brainly.com/question/13497372
#SPJ1
Use but-2-ene to illustrate the difference between e and z isomers
The but-2-ene is a molecule with four carbons and the middle bond, (the second one) is a double-bond.
So, its structure is H₃C-CH=CH-CH₃.
However, the double bond makes two possible isomers, the "e" and "z":
The double bond, differently from the single bond, does not rotate, so these structures are not the same.
In the left one, the carbon groups have higher priority, and they are in alternating sides, bottom and top, and so it is called the E isomer.
In the right one, the carbon groups are on the same side, so it is called the Z isomer.
Describe the energy transformations in each:1. When the flashlight is turned on, a flow of electrons is created by the batteries. The electricity passes through the incandescent lightbulb, causing the tungsten filament in the lightbulb to heat up. When the metal is hot enough, photons of light are emitted.
First, it is the chemical energy because of the batteries, then this energy is transforming to electrical because of the flowing of electrons. Before this, the electrical energy is going to be light energy for the light bulb and finally, we have the heat energy of the light bulb. The order is:
[tex]\text{Chemical}\to electricity\to light\to heat.[/tex]ch3)2c(oh)ch2ch3 skeletal structure, Functional groups, compound type & alcohol class if it’s an alcohol
The skeletal structure of an organic compound is an abbreviated representation of its molecular structure, they are quick and easy to draw.
For example, the following image shows the skeletal structure of a compound:
The peaks represent the carbons. We must remember that carbon can have a maximum of 4 bonds.
Now, I will show you how is the structure of this specific compound:
This is ternary alcohol, called 2-methyl-2-butanol. If you see carefully, you will notice that each carbon has 4 bonds. The functional groups present will be OH. The skeletal structure will be:
Describe a real-world example that demonstrates this relationship. In your description identify the two variables (temperature and volume) and describe how one changes as the other is increased or decreased.
A real-world example that can demonstrate the relationship between the variables temperature and volume is, for example, when we inflate a balloon for a party.
- First, we fill the ballon with a gas (air).
- Second, if we tie the balloon and heat it with some source of heat, we will see that the ballon begins to increase in volume.
So, as we increase the temperature of the gas inside the ballon, the balloon increases in volume.
This happens because temperature and volume are variables directly proportional through the Ideal Gas Law, whose formula is:
[tex]P\mathrm{}V=n\mathrm{}R\mathrm{}T[/tex]In the formula:
P is the pressure of the gas.
V is the volume of the gas.
n is the number of moles.
R is the constant of the gases.
T is the temperature of the gas.
How many moles of oxygen will be needed to combust 20.50 moles of C7H16?
Answer
225.5 mol O₂
Procedure
Assuming the complete combustion of heptane, we will consider the following reaction for our calculations.
C₇H₁₆ + 11 O₂ → 7 CO₂ + 8 H₂O
The moles of oxygen can be determined by stoichiometry
[tex]20.50\text{ mol C}_7\text{H}_{16}\frac{11\text{ mol O}_2}{1\text{ mol C}_7\text{ H}_{16}}=225.5\text{ mol O}_2[/tex]If a solution contained a substance of 4.67kg (molar mass of 34.6 g/mol) in 350mL, what is the molarity of the solution?
The molarity of a solution is the molar concentration of it.
It is calculated by:
[tex]M=\frac{n}{V}[/tex]Where n is the number of moles of the substance in the solution and V is the total volume of the solution.
The volume was given:
[tex]V=350mL=0.350L[/tex]And the number of moles we can calculate using the given mass and the molar mass:
[tex]\begin{gathered} m=4.67\operatorname{kg}=4670g \\ MM=34.6g/mol \end{gathered}[/tex]So:
[tex]\begin{gathered} MM=\frac{m}{n} \\ n=\frac{m}{MM}=\frac{4670g}{34.6g/mol}=134.97\ldots mol \end{gathered}[/tex][tex]M=\frac{134.97\ldots mol}{0.350L}=385.63\ldots mol/L\approx386mol/L[/tex]Thus, the molarity is approximately 386 mol/L.
A solution is formed by dissolving 25.0 g of NaCl in 750.0 grams of H2O.What is the mass of solute? Group of answer choices25.0 g750.0 g775.0 g
1) Solute. A solute is a substance that dissolves when put into another substance (the solvent).
NaCl dissolves when placed into water. So, NaCl is the solute.
The mass of the solute is 25.0 g.
.
what is the pH of a HCOOH solution that is 0.018m?
Answer:
[tex]pH\text{ = }2.75[/tex]Explanation:
Here, we want to get the pH of the given molecule
Firstly,we write the ionization equation so as to get the number of hydrogen atoms from its dissociation
We have this as:
[tex]HCOOH_{(aq)}+H_2O_{(l)}\rightleftarrows HCOO^-_{(aq)}+H_3O^+_{(aq)}[/tex]The Pka value for formic acid is 3.75
We have it that:
[tex]\begin{gathered} K_a=10^{-pKa} \\ K_a=10^{-3.75}\text{ = }1.78\text{ }\times10^{-4} \end{gathered}[/tex]Using the ICE equation for the equilibrium constant,we have it that:
[tex]K_a\text{ = }\frac{\lbrack HCOO^-\rbrack\lbrack H_3O^+\rbrack}{\lbrack HCOOH\rbrack\rbrack}[/tex]Thus, we have:
[tex]0.000178=\frac{x^2}{0.018\text{ - x}}^{}[/tex]Since x is very small as opposed to tthe initial acid concentration, we approximate x as 0 below
Thus,we have:
[tex]\begin{gathered} (0.018\times0.000178)=x^2 \\ x\text{ = }\sqrt[]{0.018\times0.000178} \\ x\text{ = 0.00179} \end{gathered}[/tex]Finally, we know that the pH is the negative logarithm to base 10 of the concentration of hydroxonium ion
[tex]\begin{gathered} pH=-log\lbrack H_3O^+\rbrack_{} \\ pH\text{ = -log\lbrack{}0.00179\rbrack} \\ pH\text{ = 2.75} \end{gathered}[/tex]If you have 72 moles of krb you need moles of pb(NO3) 2 use it all
Answer:
We need 36 moles of Pb(NO3)2.
Explanation:
You can see that in the chemical equation, 1 mol of Pb(NO3)2 reacts with 2 moles of KBr. If we want to know how many moles of Pb(NO3)2 we require, we have to do a rule of three, like this:
[tex]\begin{gathered} 1\text{ mol Pb\lparen NO}_3)_2\rightarrow2\text{ moles KBr} \\ ?\text{ moles Pb\lparen NO}_3)_2\rightarrow72\text{ moles KBr.} \end{gathered}[/tex]And the calculation would be:
[tex]72\text{ moles KBr}\cdot\frac{1\text{ mol Pb\lparen NO}_3)_2}{2\text{ moles KBr}}=36\text{ moles Pb\lparen NO}_3)_2.[/tex]what is the normality of a 1.5 M solution of sulfuric acid
Answer:
3N of sulfuric acid.
Explanation:
Remember that normality is a measure of concentration equal to the gram equivalent weight per liter of solution.
First, let's see the equation of normality:
[tex]Normality=Molarity\cdot\frac{molecular\text{ mass of solute}}{Equivalent\text{ mass of solute}}.[/tex]And let's see that sulfuric acid (H2SO4) is a diprotic acid because it contains 2 protons in its structure (2H+), so we're going to use this value to calculate the equivalent mass of solute.
Now, let's replace the given data: molarity is 1.5 M, the molecular mass of solute is the molecular mass of H2SO4 which is 98 g/mol (you can calculate the molecular mass of a compound using the periodic table) and the equivalent mass of solute is the division between molecular mass and the number of protons, in this case, 2:
[tex]Normality=1.5M\cdot\frac{98\text{ }\frac{g}{mol}}{\frac{98\text{ }\frac{g}{mol}}{2}}=1.5\cdot\frac{98}{49}=3\text{ N.}[/tex]The normality of this solution would be 3N.
I have tried initiating the question but I am not sure how to continue or what to do after moving things to the other side
+828kJ
Explanations:Given the following chemical reaction with their heat of reactions
[tex]\begin{gathered} 2Al(s)+\frac{3}{2}O_2(g)\rightarrow Al_2O_3(s);\text{ }\triangle H=-1675.7kJ..............\text{ 1} \\ CO(g)+\frac{1}{2}O_2(g)\rightarrow CO_2(g);\text{ }\triangle H=-282.7kJ...................2 \end{gathered}[/tex]In order to arrive at the resulting reaction, we will carry out the followiing transformation;
• Swap the reactant with product, of equation 1 and;
,• Multiply equation 2 by 3, to have;
[tex]\begin{gathered} Al_2O_3(s)\rightarrow2Al(s)+\frac{3}{2}O_2(g);\text{ }\triangle H=+1675.7kJ \\ 3CO(g)+\frac{3}{2}O_2(g)\rightarrow3CO_2(g);\text{ }\triangle H=-3(282.7)=-848.1kJ \end{gathered}[/tex]Cancel out the Oxygen element in both equation and add to have;
[tex]Al_2O_3(s)+3CO(g)\rightarrow2Al(s)+3CO_2(g);\text{ }\triangle H_{rxn}=+1675.7-848.1=+827.6kJ[/tex]Hence the enthalpy change of the reaction to 3sf is +828kJ
with the balanced equation Zn + 2HCl = H2 + ZnCl2 Calculate the moles of HCl needed to react completely with 8.25 moles of zinc.
For the reaction of Zn with HCl, the ratio is 1 mole of Zn to every 2 moles of HCl. So if there are 8.25 moles of Zn, it is possible to find the moles of HCl by doing the following relation:
1 mole Zn ----- 2 moles HCl
8.25 moles Zn ----- x moles HCl
[tex]\frac{1}{8.25}=\frac{2}{x}\Rightarrow1x=2*8.25\Rightarrow16.5\text{ moles}[/tex]16.5 moles of HCl are needed to react with 8.25 moles of zinc.
A slime mold is one of the slowest-moving organisms, traveling at top speeds of 1.02 millimeters per hour. What is the speed of a slime mold in inches per day?
We are given a speed of 1.02 mm/hr and we have to convert that speed into inches/day. To find the answer to our problem we can use a 2 steps conversion. First we can convert mm into inches and then the hr into days.
We know that there are 25.4 mm in 1 inch. So let's convert it.
25.4 mm = 1 inch
Speed = 1.02 mm/hr * 1 inch / (25.4 mm) = 0.04016 inch/hr
Speed = 0.04016 inch/hr
Then we know that there are 24 hours in 1 day.
24 hrs = 1 day
Speed = 0.04016 inch/hr * 24 hr/(1 day) = 0.964 inch/day
Speed = 0.964 inch/day
The speed of a slime mold in inches per day is 0.964.
Research: Find 4 strategies that are used to prevent rusting of car parts and/or water pipes? Briefly explain how they work in your own words. What are some pros and cons of these methods?
Question
Research: Find 4 strategies that are used to prevent rusting of car parts and/or water pipes? Briefly explain how they work in your own words. What are some pros and cons of these methods?
Answer
Method 1: Applying Oil - Coating materials with oil will help to prevent rust or slow its formation since it prevents moisture from reaching the iron, which can get oxidized.
Pros: It can be applied easily to most materials and it's of relatively low cost
Cons: Some materials can't be covered with oil because they can interfere with the process they are designed for. Example: Food transport machinery
Method 2: Paint the metal - Similarly to the oil a good amount of paint can cover the metallic parts and prevent moisture from the air to get in direct contact with the iron.
Pros: It is easy to apply paint to most metals.
Cons: Contrarily to oil, paint can be more expensive depending on the application.
Method 3: Galvanization - is the process of applying a protective zinc coating to iron or steel materials to prevent or slow the rusting processes.
Pros: The galvanization process makes steel highly durable and the material usually becomes scratch free.
Cons: Steel structures that are either too big or too small are unsuitable for the galvanization process.
Method 4: Store in a controlled environment - Metals corrode easily when exposed to environments with high humidity. To preserve a metal in good condition, it should be stored in environments with low humidity content and not in contact with salts or acids.
Pros: It does not alter the properties of the equipment.
Cons: Not all metal objects can be stored in environments containing low humidity.
Calculate the [H3O+] of the following solutions: ph = 11.8
Answer:
The [H3O+] is 1.58x10-12 M.
Explanation:
To calculate the [H3O+] from the pH, we can use the pH formula and replace the value of pH:
[tex]\begin{gathered} pH=-log{}\lbrack H_3O^+\rbrack \\ 11.8=-log\lbrack H_3O^+\rbrack \\ 10^{(-11.8)}=\lbrack H_3O^+\rbrack \\ 1.58*10^{-12}=\lbrack H_3O^+\rbrack \end{gathered}[/tex]So, the [H3O+] is 1.58x10-12 M.