Equal weights of methane and hydrogen are mixed in an empty container at 25°C. The fraction of total pressure exerted by hydrogen is:
Correct answer: B. 8/9
- A. ½
- B. 8/9
- C. 1/9
- D. 16/17
Explanation
According to Dalton's law of partial pressure, the total pressure of a mixture of gases is the sum of the partial pressure of the gases in the mixture. We can calculate the partial pressure by the following formula: Partial pressure H₂/ Partial pressure CH4 =Moles of H2/ Moles of CH4 pH2/ pCH4 = nH2/nCH4 We assume that x is the mass of hydrogen and methane each. The molecular mass of H2=2 The molecular mass of CH4=16 Mole = mass/Mr Moles of H2= x/2 Moles of CH4= x/16 Total moles= x/2 + x/16 = 9x/16 The partial pressure of H2= moles of H2/total moles =(x/2)÷(9x/16) =(x/2) x (16/9x) =8/9 so option B is the right answer.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Fundamental Concepts of Chemistry
Mole calculations connect mass, number of particles and Avogadro's number, while balanced equations provide the mole ratios used in stoichiometry. Questions cover limiting and excess reactants, theoretical yield and percentage yield, including identifying which reactant is consumed first and comparing the actual product with the maximum possible product.
Practise Fundamental Concepts of Chemistry
894 free Fundamental Concepts of Chemistry MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Fundamental Concepts of Chemistry questions
If we take 2.2g of CO2, 6.02 x 10^21 atoms of nitrogen and 0.03g atoms of sulfur, then the molar ratio of CO2, N and S atoms will be:
2 grams of H2 molecules contain _ molecules.
By heating 25g of limestone (CaCO3) , the weight of carbon dioxide produced is:
The chemical analysis of a compound having a molecular mass 188 gives, C=12.8%, H=2.1%, and Br=85.1%. Its molecular formula is:
106g of Na2CO3 per dm3 of the solution of Na2CO3 in water, the concentration of the solution will be:
What volume in dm3 of KCl is obtained in the following equation if the volume of KCIO3 at the beginning of the reaction is 20 dm3? 2KClO3 → 2KCl + 3O2