2 C2H2 + 5 O2 --> 4 CO2 + 2 H2O
2.35 mol C2H2 - x mol O2
2 mol C2H2 - 5 mol O2

answer: 5.875 mol
Just search up what makes earth’s atmosphere then you will get all the answers there
K2so4
the oxidation number of sulphur
2[1]+s+4[-2]=0
2+s-8=0
s=-6
The Yellow River is the most important water resource for the dry north of China, playing an irreplaceable role in economic development, and agriculture. Since 1960 over 14 dams have been constructed on the river for hydroelectric power, which is vital to northern China's infrastructure.