Answer:
Mass, m = 7.97 grams
Explanation:
We have,
Initial temperature was 34 degrees Celsius
Heat produced in it is 100 calories of heat
The specific heat capacity of water is 4.18 J/g °C
The heat produced due to change in temperature is given by :
m is mass of water in grams
So, 7.97 grams of water is required to produce heat of 2200 joules.
Answer:
The value of n in the hydrate formula is 5 ,
.
Explanation:
Mass of hydrate of copper sulfate = 14.220 g
Moles of hydrate of copper sulfate =
Mass of copper sulfate after heating = 8.9935 g
Moles of copper sulfate = 
Solving for n, we get:
n = 5
The value of n in the hydrate formula is 5 ,.
Answer:
0.480 grams
Explanation:
Li₃N(s) + 3D₂O (L) --------------------------> ND₃(g) + 3LiOD (aq)
1 : 3 : 1 : 3
Number of moles (n) = Mass in gram/ Molar Mass
Mass of ND₃ = 160 mg
= 0.16 g
Molar mass of ND₃= [14 + (3 x 2.014 )]
= 14 + 6.042
= 20.042 g/mol
Number of moles of ND₃ = 0.16/20.042
= 0.007983 moles
From the reaction equation, the mole ratio between Heavy water (D₂O ) and ND₃ is 3: 1.
This implies that the number of moles of Heavy water (D₂O ) required
= 3 x 0.007983 moles
= 0.023949 moles
Molar mass of Heavy water (D₂O )= [(2.014 x 2) + 16]
= 20.028 g/mol
Mass in grams of Heavy water (D₂O )= Number of moles x Molar mass
= 0.023949 x 20.028
= 0.4797 grams
≈ 0.480 grams
Answer:
Melting of ice
Explanation:
A physical change is one in which just the physical properties of the matter is altered. Most phase changes reaction falls under this type of change.
- Examples are boiling, melting, freezing, condensation, sublimation, magnetization of metals, breaking glass, cutting wood.
- No new kinds of matter is formed.
- The process is reversible
- No change in mass
