Question

2.) I mole of molecules contain ( =6.022 times 10^{23} ) Moles of ( mathrm{M}_{2} mathrm{O}=frac{2 cdot 36 times 10^{23}}{6.022 times 10^{23}}=0.392 )
Molas man of ( u_{2} 0=18 )
man of ( mathrm{M}_{2} mathrm{O}=0.392 times 18=7.05 mathrm{g} )
man of ( mathrm{Na}_{2} mathrm{SO}_{4}=15-705=7.95 mathrm{g} )
Molar man of ( mathrm{Na}_{2} mathrm{SO}_{4}=23 times 2+32 )
( +16 times 4=142 )
Moles of ( mathrm{N} a_{2}, 50_{4}=frac{7.95}{142}=0.0556 )
Mole Ratio ( mathrm{Na}_{2} mathrm{SO}_{4}=frac{0.0556}{0.0556}=1 )
( H_{2} partial=frac{0.392}{0.0556}=7 )
"Whe of ( x=7 ) foumula of compound ( =N_{12} mathrm{sO}_{4} cdot 7 mathrm{K}_{2} mathrm{O} )
the ( =(c) 7 )

# Heamoglobin contains 0.33 % iron by mass. The molecular mass of healidYIUDIIS UT 200. MON iron atoms (at mass = 56) in one molecule of heamoglobin is (A) 1 2 (B)2 (C)4 (D) 6 2. 15.0 g of a compound Na, so xH,0 contains 2.36 * 1023 H,0 molecules. What is the value of x? (A) 2 (D) 10 (B)5 . (C) 7

Solution