Answer:
how and why elements what?? why they exist?? im gonna assume that's what you meant, so elements exist because we're all on earth and without elements, we don't have resources to live. the earth is made of elements and if there were none, we wouldn't even have a planet
Explanation:
^
What is the concentration of a sodium hydroxide solution if 14.5 mL of it are exactly neutralized by 30.0 mL of a 0.500 M hydrochloric acid solution?
Answer:
1.03 M
Explanation:
Step 1: Write the balanced equation
NaOH + HCl ⇒ NaCl + H₂O
Step 2: Calculate the reacting moles of HCl
30.0 mL (0.0300 L) of 0.500 M HCl react.
0.0300 L × 0.500 mol/L = 0.0150 mol
Step 3: Calculate the moles of NaOH that react with 0.0150 moles of HCl
The molar ratio of NaOH to HCl is 1:1. The moles of NaOH that react are 1/1 × 0.0150 mol = 0.0150 mol.
Step 4: Calculate the molar concentration of NaOH
0.0150 moles of NaOH are in 14.5 mL (0.0145 L).
M = 0.0150 mol/0.0145 L = 1.03 M
Which of the changes listed below would shift this reaction to the right?
A. Decrease of pressure
B. Addition of Cl2
C. Removal of O2
D. Increase of pressure
Answer:
D: Increase of pressure
What color will the
flame turn if we
immerse a steel
wire in a barium
chloride solution and
then heat it? Why does that happen?
Answer:
Clean a platinum or nichrome (a nickel-chromium alloy) wire by dipping it into concentrated hydrochloric acid and then holding it in a hot Bunsen flame. Repeat this until the wire produces no color in the flame.
What does atom mean
A.)Consists of only electrons
B.)The smallest part of matter still retaining chemical properties
C.)Consists of only protons and neutrons
D.)Composed of two or more separate elements
Answer:
B). The smallest part of matter still retaining chemical properties.
A __________ is a feature or some influence that contributes to a result or outcome.
factor
theory
light year
spectrograph
whoever answeres all the questions will get brainliest question
question 1
why is steel not a mineral?
A. is it man-made
B. is it alive
c. is it found in nature
d. is it strong
question 2
which mineral is used to make pencils?
A. diamond
B. jade
c. graphite
d. calcite
question 3
wich mineral is used to make glass
A. emerald
b. quartz
c.copper
D. halite
question 4
wich mineral do we eat
A. silver
b. jade
c. quartz
d.halite
question 4 _____ is the hardest mineral and ____ is the softest
A. quartz, graphite
B. silver, gold
C. diamond , talc
d. halite, calcite
question 5
what is minerals streak
A. the color minerals streak
b. how much the mineral weighs
c. the shape of crystals
d. the color left behind when a mineral is
scraped on porcelain tile
question
question 6
all minerals break at the same time
a. true
b. false
Answer:
1. A
2. C
3. B
4. D
5. D
6. B
Explanation:
I'm not quiet sure on 5 but I'm pretty sure its correct
Please help im testing and need an answer as soon as possible
Kaya collects the data shown in the table.
A 2-column table with 3 rows. The first column labeled Quantity has entries Voltage, Current, Resistance. The second column labeled Value has entries 6.0 volts, 0.3 Amperes, empty.
What is the resistance in the circuit?
0.05
1.8
5.7
20
Answer:
20
Explanation:
not sure please correct me if im wrong
Answer:
20
Explanation:
Got it right on time 4 learning
The concentrations of hydrogen ion in two solutions are (a).1×10-4moldm and (b).5×10-9moldm. What is the pH of each solutions?
Answer:
(a) pH=4.0
(b) pH=8.3
Explanation:
Hello there!
In this case, since the pH is understood as the potential of the hydrogen in an aqueous solution, and we can calculate it is as follows:
[tex]pH=-log([H^+])[/tex]
We simply need to plug in the concentrations on each question as shown below:
(a)
[tex]pH=-log(1x10^{-4})\\\\pH=4[/tex]
(b)
[tex]pH=-log(5x10^{-9})\\\\pH=8.3[/tex]
Regards!
188 grams of Ca(OH)2 contain how many moles?(with calculations)
A 125.0-g sample of a metal heated to 100.0 ∘C and placed in a calorimeter that contains 250.0 g of water. The temperature rises from 24.3 ∘C to 27.2 ∘C. What is the specific heat capacity of the metal? Ignore the calorimeter in your analysis. Group of answer choices
Answer:
0.333J/g°C is the specific heat of the metal
Explanation:
The heat that the metaal gives is equal to the heat that water is absorbing. The equation is:
S(metal)*ΔT(metal)*Mass(metal) = S(H2O)*ΔT(H2O)*Mass(H2O)
Where S is specific heat, ΔT is change in temperature and mass the mass in grams of the metal and water.
Replacing:
S(metal)*(100.0°C-27.2°C)*125.0g = 4.184J/g°C*(27.2°C-24.3°C)*250.0g
S(metal) = 4.184J/g°C*(27.2°C-24.3°C)*250.0g / (100.0°C-27.2°C)*125.0g
S(metal) = 0.333J/g°C is the specific heat of the metal
what might happen if the strong force didnt exist
Answer:
Atomic nuclei would fly apart
Explanation:
A 3.5L container has a gas pressure of 5.3atm. If the volume is decreases to 1.4L. What will be the new pressure inside the container?
Answer:
your answer for that problem is 34.5
____CH4 + ____O2 ____CO2 +____H2O
[tex]methane \: reacts \: with \: oxygen [/tex]
CH4 + 2O2 → CO2 + 2H2O.
Step-by-step explanation
L.H.S.
C = 1, H = 4, O = 2×2 = 4.
R.H.S
C = 1, O = 2, H = 2×2= 4, O = 2.
Which reactant is necessary for a combustion reaction?
A. Water
O B. Heat
O c. Carbon dioxide
D. Oxygen
The reactant necessary for a combustion reaction is oxygen.
(option D).
Combustion is a chemical reaction that occurs when a substance reacts with oxygen, producing heat and light. In order for combustion to take place, three elements are needed: fuel, heat, and oxygen.
Fuel is the substance that undergoes combustion, such as gasoline, wood, or methane. Heat is the energy required to initiate and sustain the reaction. Lastly, oxygen is the reactant that combines with the fuel, allowing it to burn and release energy.
When a combustion reaction occurs, the fuel and oxygen combine to form carbon dioxide (option C) and water (option A). This process is exothermic, meaning it releases energy in the form of heat and light.
For example, when wood is burned in the presence of oxygen, it undergoes combustion. The heat from a match or a spark provides the necessary activation energy to start the reaction. Oxygen from the air combines with the carbon in the wood, producing carbon dioxide and releasing energy in the form of heat and light.
In summary, oxygen is the reactant necessary for a combustion reaction. It combines with the fuel and releases energy in the form of heat and light.
(option D).
For more such questions on combustion reaction
https://brainly.com/question/13251946
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How many grams of iron oxide, Fe2O3 will be produced if 165 g of O2 gas is supplied? (follow the same steps as mol to mol, only now your flow should be like this: grams O2 moles O2 moles Fe2O3 grams Fe2O3 Fe + O2 Fe2O3
Answer:
[tex]m_{Fe_2O_3}=549gFe_2O_3[/tex]
Explanation:
Hello there!
In this case, according to the given chemical reaction for this problem about stoichiometry:
[tex]4Fe+3O_2\rightarrow 2Fe_2O_3[/tex]
Whereas there is a 3:2 mole ratio of oxygen (molar mass = 32.0 g/mol) to iron (III) oxide (molar mass = 159.69 g/mol) and therefore, the correct stoichiometric setup is:
[tex]m_{Fe_2O_3}=165gO_2*\frac{1molO_2}{32.00gO_2}*\frac{2molFe_2O_3}{3molO_2} *\frac{159.69gFe_2O_3}{1molFe_2O_3} \\\\m_{Fe_2O_3}=549gFe_2O_3[/tex]
Regards!
What type of cell can pass a DNA mutation to an organism's offspring?
A. sex cell
B. skin cell
c. nerve cell
D. red blood cell
The answer should be sex cell.
What is the molality of a solution containing 19.5g HCl and 257g of H2O?
What is the acceleration of a 7 kg
mass being pulled by a 56 N force?
Answer:
8 meters per second per second
Explanation:
Newton's second law: [tex]f=ma[/tex], force = mass multiplied by acceleration.
Therefore 56 / 7 = acceleration = 8
What is the MOST important advantage of using ethanol as a fuel
for vehicles?
A. Ethanol reduces air pollution.
B. Ethanol mixes well with gasoline.
C. Making ethanol uses up plant products.
D. Making ethanol provides income for growers.
Answer:
The correct answer is - A. Ethanol reduces air pollution.
Explanation:
Ethanol is believed to be better fuel for the environment than other petroleum fuels. Ethanol emits lower carbon dioxide as it is clean smokeless fuel, and produces less or the same oxides of nitrogen and hydrocarbons.
It is produced by the process of fermentation of molasses by yeast. Mixing it with the other fuels is found to be CO2 reduces by 30% of emissions to the atmosphere.
which of the following can not be guessed about the prehistoric organism by its fossil ?
Answer:
Evolution in the broadest sense explains that what we see today is different from what existed in the past. Galaxies, stars, the solar system, and earth have changed through time, and so has life on earth.Something that happened in the past is thus not "off limits" for scientific study. Hypotheses can be made about such phenomena, and these hypotheses can be tested and can lead to solid conclusions. Furthermore, many key aspects of evolution occur in relatively short periods that can be observed directly—such as the evolution in bacteria of resistance to antibiotics.Laws, like facts and theories, can change with better data. But theories do not develop into laws with the accumulation of evidence. Rather, theories are the goal of science.
Explanation:
an organism that gains energy by feeding on other organism is a
A. consumer
B. predator
C. prey
D. parasite
F. host
Answer: the answer is A
Explanation:
Answer:
The answer to your question is, A. consumer.
Explanation:
Any organism that 'consumes' other organisms is a consumer
What is the number of moles of solute in 250 mL of a 0.4M solution?
a. 0.1 mol
c. 0.62 mol
b. 0.16 mol
d. 1.6 mol
Explanation:
Answer. There are 0.1 moles of solute in 250 mL of 0.4 M solution.
Calculate the volume in L of 11.6 moles of Neon at 120 K when it has a pressure of 25.9 atm
Answer:
The volume of the gas is approximately 4.41 liters
Explanation:
The details of the data of the Neon gas are;
The number of moles of Neon gas present, n = 11.6 moles
The temperature of the sample of Neon gas, T = 120 K
The pressure of the sample of the Neon gas, P = 25.6 atm
By the ideal gas equation, we have;
P·V = n·R·T
Where;
R = The universal gal constant = 0.08205 L·atm·mol⁻¹·K⁻¹
Therefore, we get;
V = n·R·T/P
Which gives;
V = 11.6 moles × 0.08205 L·atm·mol⁻¹·K⁻¹ × 120 K/(25.9 atm) ≈ 4.4097915 L
The volume of the gas, V ≈ 4.41 L.
. Which of these types of electromagnetic radiation has the lowest energy?
a. Radio waves
b. Visible light
c. Gamma rays
Why are scientists using acoustic surveys to learn about rainforest diversity
Answer:
Acoustic survey data can help inform scientists about the locations of the rainforest with the highest biodiversity. ... By working with these companies, The Nature Conservancy can help inform them of where they might try to create wildlife corridors or connected habitats on their lands
If the kinetic and potential energy in a system are equal, then the potential energy increases. What happens as a result?
Answer: As a result an increase in kinetic energy also happens.
Explanation:
Potential energy is the energy occupied by an object or substance due to its position.
Kinetic energy is the energy occupied by an object of substance due to its motion.
If the kinetic and potential energy in a system are equal and then an increase in potential energy will occur.
As a result, there will also occur an increase in kinetic energy also.
Thus, we can conclude that as a result an increase in kinetic energy also happens.
How many moles of hydrogen gas
are produced when 3.8 moles of HCI
are reacted?
O 1.9 mol
Help needed ASAP, I will mark your answer as brainly.
If 200 mL of a gas at 27 °C is cooled to -33 °C at a constant pressure, the volume will be
Answer:
V2 = 159.48 mL
Explanation:
Given the following data;
Initial volume = 200 mL
Initial temperature = 28°C
Final temperature = -33°C
To find the final volume, V2, we would use Charles law;
First of all, we would convert the temperature in Celsius to Kelvin.
Mathematically, it is given by the formula;
Kelvin = 273 + C
Substituting into the equation, we have;
Initial temperature, T1:
Kelvin = 273 + 28
Kelvin = 301K
Initial temperature, T1:
Kelvin = 273 - 33
Kelvin = 240K
To find new volume V2, we would use Charles' law.
Charles states that when the pressure of an ideal gas is kept constant, the volume of the gas is directly proportional to the absolute temperature of the gas.
Mathematically, Charles is given by;
[tex] VT = K[/tex]
[tex] \frac{V_{1}}{T_{1}} = \frac{V_{2}}{T_{2}}[/tex]
Where;
V1 and V2 represents the initial and final volumes respectively.
T1 and T2 represents the initial and final temperatures respectively.
[tex] \frac{V1}{T1} = \frac{V2}{T2}[/tex]
Making V2 as the subject formula, we have;
[tex] V_{2}= \frac{V1}{T1} * T_{2}[/tex]
[tex] V_{2}= \frac{200}{301} * 240[/tex]
[tex] V_{2}= 0.6645 * 240 [/tex]
V2 = 159.48 mL
Please help me I will really appreciate it !!!! And Please no links
Write a clear scientific explanation of how and why the water ended up on the mirror and not in the tub. Be sure to include scientific vocabulary (including any phase changes that occurred and the role of kinetic energy).
The Vocabulary words-
Condensation
Gas
Heat
Kinetic energy
Liquid
Steam
Vaporization
Water vapor
Explanation:
Steaming up or fogging happens when steam condenses on the mirror. Steam emerging from hot water can condense on a colder surface. That’s the reason you can see the result on a mirror instantaneously. Obviously, for a bathroom mirror to steam up, the steam that originates at the shower spray (or the bathtub) has to travel through the cooler air to reach the mirror. Since air tends to heat up easily, the mirror can steam up fast.