Answer: B. It must show that the mass of each element involved is conserved by a chemical reaction.
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The correct statement why a chemical equation must be balanced is It must show that the mass of each element involved is conserved by a chemical reaction.
Answer:
B. It must show that the mass of each element involved is conserved
by a chemical reaction.
Explanation:
a p e x, just took the quiz
Use Lewis dot structures to show the ionic bonding in the following pairs of elements. Show the transfer of electrons using arrows. Write the correct chemical formula for the ionic compound that forms.
1) barium oxide (Ba and O)
2) sodium oxide (Na and O)
3) calcium chloride (Ca and Cl)
4) sodium nitride (Na and N)
5) aluminum oxide (Al and O)
6) magnesium phosphide (Mg and P)
Answer:
See explanation
Explanation:
A Lewis structure is a representation of atoms of elements using dots. These dots show the number of outermost electrons in the atom. These outermost electrons are involved during ionic bonding.
We can see from the image attached that in ionic bonding, electrons are transferred from the metal to the non metal to form the ionic compound. Arrows have been used to show the transfer of electrons from metals to non metals.
The volume of a gas is 18.6 L at 0.10 atm and 273 K. Calculate the pressure in
atms of the gas if its volume is changed to 1000 ml while the temperature remains
constant?
Answer:
1.86 atm
Explanation:
The following data were obtained from the question:
Initial volume (V₁) = 18.6 L
Initial pressure (P₁) = 0.10 atm
Final volume (V₂) = 1000 mL
Final pressure (P₂) =?
NOTE: The temperature is constant.
Next, we shall convert 1000 mL to L.
1000 mL = 1 L
Finally, we shall determine the final pressure of the gas as follow:
Initial volume (V₁) = 18.6 L
Initial pressure (P₁) = 0.10 atm
Final volume (V₂) = 1 L
Final pressure (P₂) =?
P₁V₁ = P₂V₂
18.6 × 0.10 = P₂ × 1
1.86 = P₂
P₂ = 1.86 atm
Thus, the final pressure of the gas is 1.86 atm
A falling ball looses its shape and bounces off the ground because it has...Immersive Reader
Kinetic energy
Potential energy
Elastic energy
Thermal energy
what grade percentage is developing, proficient, exceeding, and emerging?
Answer:
Grade A is the best percentage that is developing, proficient, exceeding, and emerging
The percent by mass of iron(III) 1 Fe2S3
is _____%
Answer:
percent=69.94%
I need help please with the drop down menus
Answer:
When the archer releases the arrow, the elastic potential energy in the bowstring transforms into kinetic energy for the arrow.
Explanation:
When the string of a bow and arrow is pulled from equilibrium, the elastic potential energy in the bow is converted to kinetic energy of the arrow when the string is released.
whose model was discarded as a result of Rutherford's model?
A Dalton's model
B Thomson's model
C Bohr's model
D Quantum's model
Answer:
A. Dalton's model
Explanation:
Dalton's model was discarded as a result of Rutherford's model.
[tex]{ }[/tex]
[tex]\small\sf\:\:\:\:\:\:\:\:{:}\:\Longrightarrow{\bold{\pink{\sf{Thomson's \:model}}}}[/tex]
2. I need to find the angle of corner of a room, what tool could I use?
a. Combination square
b. Plumb-bob
c. Sliding t-bevel
d. Tri-square
Copper has a specific heat of 0,900 J(g C). How much energy in kJ is needed to raise the temperature of a 700 g block of aluminum from 30.7°C to 82,1C?(show your steps)
Answer:
32.4 kJ
Explanation:
Given that:
Specific heat capacity fo copper, c = 0.9
Mass of copper, m = 700 g
Temperature change, dθ ;t2 - t1 = (82.1 - 30.7) = 51.4
Energy required, E = mcdθ
E = 700 * 0.9 * 51.4
E = 32382 J
Energy required on kJ
32382 / 1000
= 32.382 kJ
= 32.4 kJ
One of the following is not a physical property of iron.
Mark only one oval.
malleability
magnetism
rusting
color
Answer:
Rusting
Explanation:
Rusting is oxidizing iron, which would be a chemical property.
Mercury(II) oxide decomposes to form mercury and oxygen, like this:
2Hg (l) + O2 (g) → 2HgO (s)
At a certain temperature, a chemist finds that a reaction vessel containing a mixture of mercury(II) oxide, mercury, and oxygen at equilibrium has the following composition:
compound amount
Hg 14.7g
O2 13.4g
HgO 17.8g
Calculate the value of the equilibrium constant for this reaction. Round your answer to significant digits. Clears your work. Undoes your last action. Provides information about entering answers.
Solution :
For the reaction given :
[tex]$\text{2Hg}_{(l)}+\text{O}_2_{(g)} \rightarrow \text{2HgO}_{(s)}$[/tex]
Thus we know that the equilibrium constant [tex]$K_c$[/tex] contains aqueous an dgas species only.
∴ [tex]$K_c=\frac{1}{[O_2]}$[/tex] ............(1)
Now at the equilibrium, an amount of the 13.4 g of oxygen was found in the vessel of 6.9 liters. For determining the concentration of the oxygen gas, we use :
[tex]$[O_2]= \frac{n_{O_2}}{V_{soln}}$[/tex] ................... (2)
Here, [tex]$n_{O_2}$[/tex] = no. of moles of oxygen gas (mol)
[tex]$V_{soln}$[/tex] = volume of solution (L)
Therefore the number of moles of the oxygen gas is calculated by directly using the molecular weight (31.9988 g/mol) as the conversion factor.
∴ [tex]$n_{O_2}= 13.4 \ g \times \frac{\text{1 mol}}{31.9988 \ g}$[/tex]
= 0.418 mol
Now substituting the known values in (2), we can find the equilibrium concentration of the oxygen gas :
[tex]$[O_2] =\frac{0.418 \ \text{mol}}{6.9 \ \text{L}}$[/tex]
= 0.0605 M
Therefore substituting the result in (1), the equilibrium constant for the reaction is :
[tex]$K_c=\frac{1}{0.0605}$[/tex]
= 16.52
Please help me thanks so much
Answer:
a switch
Explanation:
Answer:
a switch is the answer hope it helps
How does shaking or stirring a mixture of solute and solvent affect a solution?
CA. It increases the solubility of the solute.
CB. It increases the rate of dissolving.
C C. It decreases the solubility of the solute.
D. it decreases the rate of dissolving.
Which part of the kite catches the wind?
a Cover
b Frame
c Tail
d Kite string
Answer:
cover A
Explanation:
Answer:
cover sorry if im wrong
Explanation:
the cover makes the kiete float using air resisance
Guys please help me i will mark brainly!
Answer:
D
Explanation:
Which materials allow electrons to flow through them?
A. Insulators only
B. Semiconductors and conductors
C. Conductors only
D. Semiconductors and insulators
The materials which allow electrons to flow through them are Semiconductors and conductors. Hence Option (B) is correct.
What are conductors ?A conductor, or electrical conductor, is a substance or material that allows electricity to flow through it.
In a conductor, electrical charge carriers, usually electrons or ions, move easily from atom to atom when voltage is applied.
Therefore, The materials which allow electrons to flow through them are Semiconductors and conductors. Hence Option (B) is correct.
Learn more about Conductor here ;
https://brainly.com/question/8426444
#SPJ5
Answer:semiconductors and conductors
Explanation:
Scientists often use controlled experiments to answer questions. Choose ALL correct statements about controlled experiments. A) No changes are made to a test group in an experiment. B) A control group is used for comparison to other groups. C) Only one change can be made per test group in an experiment. D) Changes can only be made to the control group in an experiment. E) A controlled experiment must have a control group and test group(s).
Answer:
B) A control group is used for comparison to other groups.
E) A controlled experiment must have a control group and test group(s).
Explanation:
Answer:
B & E should be the answers
Which units can be used to measure length or distance? Check all that apply.
gram
meter
kilometer
liter
inch
Answer:
Meter, kilometer & inch - used to measure length or distance.
3. What is the difference between prodation and competition?
a. Competition is the demand for the same resource, precision is when one
organism eats another
b. Competition is when one organism eats another, predation is the demand for the
same resource
C. Competition always ends with one organismiling another, while predation is
when one organism just harms another
d. None of the above
An empty steel container is filled with 2.0 atm of H₂ and 1.0 atm of F₂. The system is allowed to reach equilibrium according to the reaction below. If Kp = 0.45 for this reaction, what is the equilibrium partial pressure of HF?
The equilibrium partial pressure of HF is 0.55 atm.
The equation of the reaction is;
H2(g) + F2(g) ⇄ 2HF
I 2 1 0
C -x -x +x
E 2 - x 1 - x x
We know that;
pH2 = 2.0 atm
PF2 = 1.0 atm
pHF = ??
Kp = 0.45
So;
Kp = (pHF)^2/pH2. pF2
0.45 = x^2/(2 - x) (1 - x)
0.45 = x^2/x^2 - 3x + 2
0.45(x^2 - 3x + 2) = x^2
0.45x^2 - 1.35x + 0.9 = x^2
0.55 x^2 + 1.35x - 0.9 = 0
x = 0.55 atm
Learn more about equilibrium: https://brainly.com/question/3980297
a furnace is thermal energy
A. True
B. False
Answer: true
Explanation:
Thermal efficiency of process heating equipment
Sam and Jane have been investigating the amount of copper sulphate that can be dissolved in water at different temperatures .They added copper sulphate till it could not be dissolved any further and also measured the mass of copper. The results are below. What conclusions can you make from results?
Answer:
This question is so confusing, I'm sorry
You pump 100 gas particles in Basketball A and 100 gas particles in Basketball B. both basketballs are at room temperature ¿Which basketball will be more firm? ¿And Why?
Answer:
I think the answer is probably b
Which one of the following represents an acceptable set of quantum numbers for an electron in an atom? (arranged as n, l, ml, and ms)
2, 2, -1, -1/2
3, 3, 3, 1/2
3, 3, 3, -1/2
5, 4,- 5, 1/2
2, 1, 0, 1/2
hi, if your looking for extra points (50+) and brainiest here is ur chance, answer this question correctly plz
Answer:
Answer choice 'C'
Explanation:
As the ball slows after kicking generates maximum Kinetic Energy, the ball slows due to its Kinetic Energy being transferred to surroundings because of atmospheric and surface friction until it stops in a state of static equilibrium.
A 50.0-mL volume of 0.15 M HBr is titrated with 0.25 M KOH. Calculate the pH after the addition of 13.0 mL of KOH. Express your answer numerically.
Answer:
pH= 1.17
Explanation:
The neutralization reaction between HBr (acid) and KOH (base) is given by the following equation:
HBr(aq) + KOH(aq) → KBr(aq) + H₂O(l)
According to this equation, 1 mol of HBr reacts with 1 mol of KOH. Then, the moles can be expressed as the product between the molarity of the acid/base solution (M) and the volume in liters (V). So, we calculate the moles of acid and base:
Acid:
M(HBr) = 0.15 M = 0.15 mol/L
V(HBr) = 50.0 mL x 1 L/1000 mL = 0.05 L
moles of HBr = M(HBr) x V(HBr) = 0.15 mol/L x 0.05 L = 7.5 x 10⁻³ moles HBr
Base:
M(KOH) = 0.25 M = 0.25 mol/L
V(HBr) = 13.0 mL x 1 L/1000 mL = 0.013 L
moles of HBr = M(HBr) x V(HBr) = 0.25 mol/L x 0.013 L = 3.25 x 10⁻³ moles KOH
Now, we have: 7.5 x 10⁻³ moles HBr > 3.25 x 10⁻³ moles KOH
HBr is a strong acid and KOH is a strong base, so they are completely dissociated in water: the acid produces H⁺ ions and the base produces OH⁻ ions. So, the difference between the moles of HBr and the moles of KOH is equal to the moles of remaining H⁺ ions after neutralization:
moles of H⁺ = 7.5 x 10⁻³ moles HBr - 3.25 x 10⁻³ moles KOH = 4.25 x 10⁻³ moles H⁺
From the definition of pH:
pH = -log [H⁺]
The concentration of H⁺ ions is calculated from the moles of H⁺ divided into the total volume:
total volume = V(HBr) + V(KOH) = 0.05 L + 0.013 L = 0.063 L
[H⁺] = (moles of H⁺)/(total volume) = 4.25 x 10⁻³ moles/0.063 L = 0.067 M
Finally, we calculate the pH after neutralization:
pH = -log [H⁺] = -log (0.067) = 1.17
What is the mass of 8.56 x 10^23 formula units of BaBr2? (3 sig figs in your answer)
296 g BaBr₂
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Reading a Periodic TableMolesAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisExplanation:Step 1: Define
[Given] 8.56 × 10²³ formula units BaBr₂
[Solve] grams BaBr₂
Step 2: Identify Conversions
Avogadro's Number
[PT] Molar Mass of Ba - 137.33 g/mol
[PT] Molar Mass of Br - 35.45 g/mol
Molar Mass of BaBr₂ - 137.33 + 2(35.45) = 208.23 g/mol
Step 3: Convert
[DA} Set up: [tex]\displaystyle 8.56 \cdot 10^{23} \ formula \ units \ BaBr_2(\frac{1 \ mol \ BaBr_2}{6.022 \cdot 10^{23} \ formula \ units \ BaBr_2})(\frac{208.23 \ g \ BaBr_2}{1 \ mol \ BaBr_2})[/tex][DA] Multiply/Divide [Cancel out units]: [tex]\displaystyle 295.99 \ g \ BaBr_2[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
295.99 g BaBr₂ ≈ 296 g BaBr₂
Thank you agenthammerx for helping me with this question!
Answer:
296 g BaBr₂
General Formulas and Concepts:
Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction
Left to Right
Chemistry
Atomic Structure
Reading a Periodic Table
Moles
Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
Stoichiometry
Using Dimensional Analysis
Explanation:
Step 1: Define
[Given] 8.56 × 10²³ formula units BaBr₂
[Solve] grams BaBr₂
Step 2: Identify Conversions
Avogadro's Number
[PT] Molar Mass of Ba - 137.33 g/mol
[PT] Molar Mass of Br - 35.45 g/mol
Molar Mass of BaBr₂ - 137.33 + 2(35.45) = 208.23 g/mol
Step 3: Convert
[DA} Set up:
[DA] Multiply/Divide [Cancel out units]:
Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
295.99 g BaBr₂ ≈ 296 g BaBr₂
number of molecules in lithium sulfate Li2So4
State the coefficient required to correctly balance the following chemical equation:
__KCI + __Fe —-> __FeCI2+ __K
Answer:
2KCl+Fe---->FeCl2+2K
Explanation:
You can observe that the no.of atoms in reactant side is equal to that of products side of each element.
Select the correct answer.
Which of these is always equal to the molar mass of any element?
OA
its atomic number
B.
its atomic weight
OC.
its atomic formula
OD.
its atomic structure
Answer:
a t o m i c w e i h g t
B
Explanation:
a to m i c w e i g h t