The question is incomplete. The complete question is:
Calcium Carbide (CaC₂) is an unusual substance that contains a carbon anion (C₂²⁻). The reaction with water involves several steps that occur in rapid succession. CaC2 is a salt (notice that its name is similar to sodium chloride). When a salt dissolves in water, ions leave the crystal lattice and enter the aqueous (aq) solution. Write the relevant balanced chemical equation for the dissolution of CaC₂, in water.
Answer:
CaC₂(s) + 2H₂O(l) → Ca(OH)₂(aq) + C₂H₂(aq)
Explanation:
When a salt dissolves in water, it dissociates in its ions. In the Calcium Carbide, the cation is Ca⁺² and the anion is C₂²⁻, so the reaction is:
CaC₂(s) + 2H₂O(l) → Ca(OH)₂(aq) + C₂H₂(aq)
The base Ca(OH)₂ is soluble, so it will dissociate at Ca⁺ and OH⁻, but the C₂H₂ is stable and doesn't dissociate in the solution.
The relation between density and mass and volume is

the dose required is 2.5 tsp
each tsp contain 5mL
So dose required in mL = 2.5 X 5 = 12.5 mL
the mass will be calculated using following formula


The mass of dose in grams will be 15.38 g
Formula:

Given:
Density=3.4
Volume=500.0
Plug them into the formula:
Final answer: 1700g
<u>Answer:</u> The percent composition of hydrogen in the sample is 15.22 %
<u>Explanation:</u>
We are given:
Mass of hydrogen = 7 grams
Mass of nitrogen = 32 grams
Mass of carbon = 7 grams
Total mass of the sample = 7 + 32 + 7 = 46 grams
To calculate the percentage composition of hydrogen in sample, we use the equation:

Mass of sample = 46 g
Mass of hydrogen = 7 g
Putting values in above equation, we get:

Hence, the percent composition of hydrogen in the sample is 15.22 %