This problem is asking for the percent by mass of hydrogen in hydrofluoric acid. At the end, the answer turns out to be D. 5% as shown below:
<h3>Percent compositions:</h3>
In chemistry, percent compositions are used for us to know the relative amount of a specific element in a compound. In order to do so for hydrogen, we use the following formula, which can also be applied to any other element in a given compound:
Where 
stands for the atomic mass of hydrogen and 
for the molar mass of hydrofluoric acid. In such a way, we plug in the atomic masses of hydrogen (1.01 g/mol) and fluorine (19.0 g/mol) to obtain:
Learn more about percent compositions: brainly.com/question/12247957
Answer:
The answer to your question is below
Explanation:
Factors that affect the rate of a chemical reaction
- Temperature If the temperature increases the rate of reaction increases.
- Concentration The reaction will move where there less concentration it could be to the reactants of products.
- Particle size The lower the particle size the higher the rate of reaction.
- Catalyst Catalyzers accelerate the rate of reaction
- Pressure The reaction will move where there are fewer molecules.
Answer:
There are 2 atoms in NaCl. This is because there is 1 atom of Na (sodium) and 1 atom of Cl (chlorine) in each NaCl molecule. Elements by themselves do not have a "number of atoms"- if you're talking about the atomic number, it's the number of protons (or electrons in a neutral atom) of an element.
2.5LX2 M=5 moles
As Molarity X Volume= Total Number of Moles
