The reaction of iron sulfide (FeS) with hydrochloric acid (HCl) results in the formation of ferrous chloride (FeCl2) and hydrogen sulfide (H2S) gas. The reaction can be shown as follows:
FeS (s) + HCl(aq) ---- FeCl2(s) + H2S(g)
The bubbles indicate the formation of H2S gas which is a chemical change. The formation of bubbles indicates this change as it suggests that the reactants are combing to form products i.e. it signals a chemical reaction.
Answer:
pH → 7.46
Explanation:
We begin with the autoionization of water. This equilibrium reaction is:
2H₂O ⇄ H₃O⁺ + OH⁻ Kw = 1×10⁻¹⁴ at 25°C
Kw = [H₃O⁺] . [OH⁻]
We do not consider [H₂O] in the expression for the constant.
[H₃O⁺] = [OH⁻] = √1×10⁻¹⁴ → 1×10⁻⁷ M
Kw depends on the temperature
0.12×10⁻¹⁴ = [H₃O⁺] . [OH⁻] → [H₃O⁺] = [OH⁻] at 0°C
√0.12×10⁻¹⁴ = [H₃O⁺] → 3.46×10⁻⁸ M
- log [H₃O⁺] = pH
pH = - log 3.46×10⁻⁸ → 7.46
Answer:A pseudo-noble gas configuration is: 1s2 2s2 2p6 3s2 3p6 3d10. Cu^+ has this electron configuration. The answer is C)
Explanation:
Answer:
Option B = 60,600 mg (correct option)
Explanation:
First of all we will have an idea which numbers are consider as significant.
1 = All non-zero digits are consider significant figures like 1, 2, 3, 4, 5, 6, 7, 8, 9.
2= Leading zeros are not consider as a significant figures. e.g. 0.02 in this number only one significant figure present which is 2.
3= Zero between the non zero digits are consider significant like 105 consist of three significant figures.
4= The zeros at the right side e.g 3400 are also significant. There are four significant figures are present.
In given options, Option A 60.6 mg have 3 significant figures.
Option B have 5 significant figures.
Option C have 4 significant figures.
Option D have 3 significant figures.
Thus option b is correct option which have more significant figures.
