There are two hydrogen and two oxygen molecules because the number next to the atomic number is how many there are.
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Answer:</h3>
200 mL
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Explanation:</h3>
Concept tested: Dilution formula
We are given;
- Concentration of stock solution as 1.00 M
- Volume of the stock solution as 50 mL
- Molarity of the dilute solution as 0.25 M
We are required to calculate the volume of diluted solution;
- The stock solution is the original solution before dilution while diluted solution is the solution after dilution.
- Using the dilution formula we can determine the volume of diluted solution;
M1V1 = M2V2
Rearranging the formula;
V2 = M1V1 ÷ M2
= (1.00 M × 50 mL) ÷ 0.25 M
= 200 mL
Therefore, a volume of 200mL of 0.25 M solution could be made from the stock solution.
These are the answer options of this question and the comments about their validity:
<span>A) It dictates that the number of molecules on each side of a chemical equation must be the same.
False: the number of molecules can change. Take this simple reaction for example:
2H2(g) + O2 -> 2H2O
You start with 3 molecules, 2 molecules of H2 and 1 molecule of O2, and end with 2 molecules of water. Then the number of molecules of each side is different.
B) It dictates that the number of atoms of each element must be the same on both sides of a chemical equation.
TRUE: in a chemical reaction the atoms remain being the same at start and at the end of the process. Given that each atom has a characteristic mass, their conservation implies the law of conservation mass.
C) It states that the mass of the reactants must remain constant in order for a chemical reaction to proceed.
FALSE. The mass of the reactants changes during a chemical reaction, while they transform into the products.
D) It does not apply to chemical reactions.
FALSE: It is an important law used in the calculus related with chemical reactions.
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The balanced equation would be
3H2 + N2 ———> 2NH3
Answer:
Respiration is considered as exothermic reaction because energy is released in this process. Glucose combines with oxygen present in our cells to form carbon dioxide and water along with energy.
Explanation:
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