1 What is the concentraion of H+ ions in 0.05mol/dm3 sulphuric acid? (not sure how to calculate)
A 0.025 g/dm3 B 0.05 g/dm3 C 0.10 g/dm3 D 2.0 g/dm3
2 Propane burns completely in O2 to produce CO2 and 4H2O.
If 0.1 mol of propane has is burnt completely, which volume of gaseous product is obtained, measured at r.t.p?
I have the ans as 7.2dm3 but the ans given was 0.1dm3
3 Which ion is present in the highest concentration in a 2mol/dm3 aq. solution of Na2SO4?
hydrogen ion, hydroxide ion, sodium ion or sulphate ion
3 All ammonium salts on heating with sodium hydroxide produce ammonia gas. From which ammonium salt can the greatest mass of NH3 be obtained?
A 0.5 mol (NH4)3PO4
A 0.5mol(NH4)2SO4
C 1.0 mol NH4Cl
D1.0mol NH4NO3
Do I have to write out the equation one-by-one to get the answer? I am not sure of the products for some reactants. Or maybe there's some other way?
4 Which quantity is the same for 1 mole of ethanol and 1 mole of ethane
The answer is the number of molecules (other options include mass, no. of atoms, and volume at r.t.p) I wrote volume but still don't know why I got it wrong. I mean yea surely ethanol can't exist as gas so maybe volume is not the wrong answer but why no. of molecules?
I know this is a long list of questions but I am preparing for a chem exam tomorrow so would need help asap. Thanks!
Originally posted by anpanman:1 What is the concentraion of H+ ions in 0.05mol/dm3 sulphuric acid? (not sure how to calculate)
A 0.025 g/dm3 B 0.05 g/dm3 C 0.10 g/dm3 D 2.0 g/dm3
2 Propane burns completely in O2 to produce CO2 and 4H2O.
If 0.1 mol of propane has is burnt completely, which volume of gaseous product is obtained, measured at r.t.p?
I have the ans as 7.2dm3 but the ans given was 0.1dm3
3 Which ion is present in the highest concentration in a 2mol/dm3 aq. solution of Na2SO4?
hydrogen ion, hydroxide ion, sodium ion or sulphate ion
3 All ammonium salts on heating with sodium hydroxide produce ammonia gas. From which ammonium salt can the greatest mass of NH3 be obtained?
A 0.5 mol (NH4)3PO4
A 0.5mol(NH4)2SO4
C 1.0 mol NH4Cl
D1.0mol NH4NO3
Do I have to write out the equation one-by-one to get the answer? I am not sure of the products for some reactants. Or maybe there's some other way?
4 Which quantity is the same for 1 mole of ethanol and 1 mole of ethane
The answer is the number of molecules (other options include mass, no. of atoms, and volume at r.t.p) I wrote volume but still don't know why I got it wrong. I mean yea surely ethanol can't exist as gas so maybe volume is not the wrong answer but why no. of molecules?
I know this is a long list of questions but I am preparing for a chem exam tomorrow so would need help asap. Thanks!
1) C i think cos there are 2H+ for every H2SO4
2) C3H8 + 5O2 -> 3CO2 + 4H2O
0.1mol of propane is already 2.4dm3 so i don't see how the answer can be just 0.1dm3
3) a) U get the most NH3 from it. 1.5 mole compared to 1 mol for b, c, d
4) 1 mole of any substance means it has 6.023X10^23 molecules.
Mass is obviously different due to Mr
Number of atoms is different as well since ethanol has 1 more atom than ethane
Vol is wrong since they are of different states.