Formulae, atoms and titrations

0 of 10 answered, 0 correct

1. Question 1 of 10

   The ethanedioate ion has the formula C₂O₄²⁻. What is the formula of iron(III) ethanedioate?

   AA, FeC₂O₄BB, Fe₂(C₂O₄)₃CC, Fe₃(C₂O₄)₂DD, Fe(C₂O₄)₃

2. Question 2 of 10

   What is the oxidation number of vanadium in NH₄VO₃?

   AA, +3BB, +4CC, +5DD, +6

3. Question 3 of 10

   Which is the correct balanced equation for aluminium reacting with dilute sulfuric acid?

   AA, 2Al + 3H₂SO₄ → Al₂(SO₄)₃ + 3H₂BB, Al + H₂SO₄ → AlSO₄ + H₂CC, 2Al + 3H₂SO₄ → Al₂(SO₄)₃ + 6H₂DD, 2Al + 6H₂SO₄ → 2Al(SO₄)₃ + 6H₂

4. Question 4 of 10

   A radioisotope has a half-life of 15 hours. What mass remains from a 12.0 g sample after 60 hours?

   AA, 0.75 gBB, 1.50 gCC, 3.00 gDD, 0.375 g

5. Question 5 of 10

   The first five ionisation energies of element Z are 738, 1451, 7733, 10541 and 13630 kJ mol⁻¹. What is the formula of the oxide of Z?

   AA, Z₂OBB, ZOCC, Z₂O₃DD, ZO₂

6. Question 6 of 10

   How many orbitals are occupied in a ground-state sulfur atom?

   AA, 5BB, 8CC, 9DD, 16

7. Question 7 of 10

   In the hydrogen emission spectrum, why do the lines within a series get closer together at higher frequency?

   AA, The energy levels get closer together at higher energyBB, Electrons move faster in higher energy levelsCC, Fewer electrons are excited to higher energy levelsDD, Lines from different series overlap

8. Question 8 of 10

   A student's titres were: rough 23.40 cm³, run 1 22.85 cm³, run 2 23.35 cm³, run 3 22.90 cm³. What is the mean titre?

   AA, 22.88 cm³BB, 23.03 cm³CC, 23.13 cm³DD, 23.10 cm³

9. Question 9 of 10

   25.0 cm³ of sodium hydroxide solution is neutralised by 18.40 cm³ of 0.150 mol dm⁻³ sulfuric acid. What is the concentration of the sodium hydroxide?

   AA, 0.110 mol dm⁻³BB, 0.204 mol dm⁻³CC, 0.221 mol dm⁻³DD, 0.442 mol dm⁻³

10. Question 10 of 10

    A student rinses a burette with distilled water but not with the acid before filling it with the acid. What is the effect on the titre?

    AA, It is larger, because the acid is dilutedBB, It is smaller, because the acid is dilutedCC, There is no effect, because the moles of acid are unchangedDD, It is larger, because the water reacts with the alkali