Answer:
Hydrogen gas
Explanation:
During electrolysis of acidified water, H+ ions are reduced to H2 gas at the negative carbon electrode (cathode) and hence hydrogen gas is liberated at cathode.
Answer:

Explanation:
We have two pressures, two temperatures, and one volume.
This looks like a question in which we can use the Combined Gas Law to calculate the volume.

Data:

Calculation:

Answer:
V = 3.1 L
Explanation:
Given data:
Molarity of solution = 0.37 M
Mass of LiF = 29.53 g
Volume of solution = ?
Solution:
Number of moles of LiF:
Number of moles = mass/molar mass
Number of moles = 29.53 g/ 25.94g/mol
Number of moles = 1.14 mol
Volume:
Molarity = number of moles of solute / Volume in L
0.37 M = 1.14 mol / V
V = 1.14 mol / 0.37 M
V = 3.1 L (M = mol/L)
Answer:
c = 0.898 J/g.°C
Explanation:
1) Given data:
Mass of water = 23.0 g
Initial temperature = 25.4°C
Final temperature = 42.8° C
Heat absorbed = ?
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
Specific heat capacity of water is 4.18 J/g°C
ΔT = 42.8°C - 25.4°C
ΔT = 17.4°C
Q = 23.0 g × × 4.18 J/g°C × 17.4°C
Q = 1672.84 j
2) Given data:
Mass of metal = 120.7 g
Initial temperature = 90.5°C
Final temperature = 25.7 ° C
Heat released = 7020 J
Specific heat capacity of metal = ?
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 25.7°C - 90.5°C
ΔT = -64.8°C
7020 J = 120.7 g × c × -64.8°C
7020 J = -7821.36 g.°C × c
c = 7020 J / -7821.36 g.°C
c = 0.898 J/g.°C
Negative sign shows heat is released.