Question

1. Which of the following metals is present in
the anode mud during the electrolytic refining
of copper?
(a) Sodium (b) Aluminium (e) Gold (d) Iron
2. An element reacts with oxygen to give a
compound with a high melting point. The
compound is soluble in water. The element is
likely to be
(a) calcium (b) carbon (c) iron (d) silicon
3. The second most abundant metal in the
earth's crust is
(a) oxygen (b) silicon (c) aluminium (d) iron
4. An alloy of Zn and Cu is dissolved in dil
HC1. Hydrogen gas is evolved. In this
evolution of gas
(a) only zinc reacts with dil. HC1 (b) only
copper reacts with dil. HC1
(c) both zinc and copper react with dil HC1
(d) only copper reacts with water
5. A greenish coating develops on copper
utensils due to formation of
(a) CUCo3 (b) Cu(OH)2 (c) Cu(OH)2.cucoa
(d) Cuo
6. Rusting of iron takes place in
(a) ordinary water (b) distilled water
(c) both ordinary and distilled water (d) none​

Answer 1

Answer:

Answer

Explanation:

E - gold

Because they are less reactive

2 question

A- calcium

Because:- calcium reacts with oxygen to give calcium oxide which is dissolved in water to give lime water.

3-question

A-: only

B- silicon

Because - : Silicon is the second most common element present in the crust with an abundance of 276,900 ppm.

4:- question

A-: only zinc react with dil hcl

5-:question

A-:cuco3

6-:question

C-: ordinary and distilled water