Answer:
a) 2NaOH(aq) + CuSO4(aq) -------------> Cu(OH)2(s) + Na2SO4(aq)
b) Ca(OH)2(aq) + CO2(g) --------------> CaCO3 + H2O (this is already balanced)
c) Pb(NO3)2 + H2SO4 --------> PbSO4 + 2HNO3.
d) 2KNO3 ------> 2KNO2 + O2
e) H2SO4 + 2(NaOH) -----> Na2SO4 + 2(H2O)
f) Ca(NO3)2(aq) + (NH4)2CO3(aq) ----------------> CaCO3(s) + 2NH4NO3(aq)
Answer:
Empirical CHO2
Molecular C2H2O4
Explanation:
To determine the formulas, firstly, we need to divide the percentage compositions by the atomic masses.
Kindly note that the atomic mass of carbon, oxygen and hydrogen are 12, 16 and 1 respectively. We proceed with the division as follows:
C = 26.7/12 = 2.225
H = 2.2/1 = 2.2
O = 71.1/16 = 4.44375
We then proceed to divide by the smallest value which is 2.2 in this case
C = 2.25/2.2 = 1
H = 2.2/2.2 = 1
O = 4.44375/2.2 = 2
Thus, the empirical formula is CHO2
We now proceed to get the molecular formula as follows
[12+ 1 + 16(2) ]n = 90.04
45n = 90.04
n = 90.04/45 = 2
The molecular formula is :
C2H2O4
mol=35:101.11 g/mol=0.346
formula units = 0.346 x 6.02 x 10²³ = 2.082 x 10²³
Answer: 39 electrons
Explanation: Subtract 79 by 40 to get the atomic number (amount of protons) which is 39. The number of electrons must be the same as the number of protons if it's not an ionic compound so the amount of electrons is the same amount of protons.
