Answer:
Number of moles of iron are 4 mol.
Explanation:
Given data:
Mass of iron = 223.4 g
Number of moles = ?
Solution:
Molar mass of iron = 55.85 g/mol
Formula:
Number of moles = mass/molar mass
Number of moles = 223.4 g/ 55.85 g/mol
Number of moles = 4 mol
Latent heat of fusion for ice is 33600J/k
Heat absorbed
- k_f×m
- 31.6×33600
- 1061,740mJ
- 1061J
Answer:
Explanation:
To determine the age, we need to know how much U have become Pb, so first we have to calculate the Pb moles present in a sample:
The percentage of U degradation:
Assuming that the life time is linear:
The question is incomplete, the complete question is;
Calculate the volume of concentrated HCL (12 M) needed to convert 1.5 g of sodium benzoate back to benzoic acid.
Answer:
8.33 * 10^-4 L
Explanation:
Equation of the reaction;
C6H5COONa + HCl -------->>>> C6H5COOH + NaCl
Number of moles of sodium benzoate = mass/molar mass
molar mass of sodium benzoate =144.11 g/mol
mass of sodium benzoate = 1.5 g
Number of moles of sodium benzoate = 1.5g/144.11 g/mol
Number of moles of sodium benzoate = 0.01 moles
Since the reaction is 1:1, 0.01 moles of HCl reacted.
but;
n = CV
n = number of moles
C = concentration
V = volume
V = n/C
V = 0.01 moles/12 M
V = 8.33 * 10^-4 L
