Chemistry

ZnO(s) + CO(g) → Zn(s) + CO2(g). What happens to Zinc?

A. decomposed B. displaced C. oxidized D. reduced Correct Answer: Option D - reduced

5 years ago

The oxidation state of chlorine in HClO4 is?

A. -5 B. -1 C. +1 D. +7 Correct Answer: Option D = +7

5 years ago

What volume of 0.5 mol dm−³ H2SO4 will exactly neutralize 20cm³ of 0.1 mol dm−³ NaOH solution?

A. 2.0 cm³ B. 5.0 cm³ C. 6.8 cm³ D. 8.3 cm³ Correct Answer: Option A - 2.0 cm³ Explanation…

5 years ago

Which of the following compound is a normal salt?

A. NaHS B. NaHSO4 C. NaHCO3 D. Na2CO3 Correct Answer: Option D - Na2CO3

5 years ago

Calcium tetraoxosulphate (VI) dissolves in water only sparingly to form a?

A. solution B. suspension C. precipitate D. colloid Correct Answer: Option C - precipitate

5 years ago

The solubility in mol dm−³ of 20g of CuSO4 dissolved in 100g of water at 180°C is [Cu = 64, S = 32, O =16]

A. 0.13 B. 0.25 C. 1.25 D. 2.00 Correct Answer: Option C - 1.25 Explanation Relative molecular mass of CuSO4…

5 years ago

A carcinogenic substance is?

A. asbestos dust B. sawdust C. nitrogen (II) oxide D. carbon (II) oxide Correct Answer: Option A - asbestos dust…

5 years ago

Pollution of underground water by metal ions is very likely in the soil that has high?

A. acidity B. alkalinity C. chloride content D. nitrate content Correct Answer: Option D - nitrate content

5 years ago

Hardness of water is caused by the presence of ions of?

A. magnesium and silver B. calcium and magnesium C. sodium and potassium D. calcium and sodium Correct Answer: Option B…

5 years ago

Which of the following mixture of gases is likely to burn in flame?

A. neon and hydrogen B. nitrogen and helium C. helium and neon D. neon and nitrogen Correct Answer: Option A…

5 years ago