Calcium hydride reacts with water to form calcium hydroxide (aqueous) and hydrogen gas. How would you write a balanced chemical equation for the reaction? How many grams of calcium hydride are needed to form 4.600 of hydrogen?
Approx.
By signing up, you agree to our Terms of Service and Privacy Policy
Sure, here are the answers:
-
Balanced chemical equation: [ \ce{CaH2 + 2H2O -> Ca(OH)2 + 2H2} ]
-
To find the grams of calcium hydride needed to form 4.600 g of hydrogen: [ \text{Molar mass of } \ce{CaH2} = 42.09 \text{ g/mol} ] [ \text{Molar mass of } \ce{H2} = 2.02 \text{ g/mol} ] [ \text{Moles of } \ce{H2} = \frac{4.600 \text{ g}}{2.02 \text{ g/mol}} \approx 2.277 \text{ mol} ] According to the balanced equation, 1 mol of (\ce{CaH2}) produces 2 mol of (\ce{H2}). So, moles of (\ce{CaH2}) needed = (2.277 \text{ mol} \times \frac{1 \text{ mol } \ce{CaH2}}{2 \text{ mol } \ce{H2}} = 1.138 \text{ mol}) [ \text{Mass of } \ce{CaH2} = 1.138 \text{ mol} \times 42.09 \text{ g/mol} \approx 47.93 \text{ g} ] So, approximately 47.93 grams of (\ce{CaH2}) are needed to form 4.600 grams of (\ce{H2}).
By signing up, you agree to our Terms of Service and Privacy Policy
When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.
When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.
When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.
When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.

- 98% accuracy study help
- Covers math, physics, chemistry, biology, and more
- Step-by-step, in-depth guides
- Readily available 24/7