Calculate the volume of carbon (IV) oxide evolved at s. t.p(standard temperature and pressure) when 21g of sodium hydrogen trioxocarbonate (IV) is heated. [H=1,C=12, Na=23, O=16, molar volume(Vm)=22.4dm cube per mol]

the formula would be mgso4

mgso[subscript]4

answer; /// the amount of material dissolved in a measure of liquid(concentration) the above statement is (true); /// good luck

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2