(he)art.

(he)art.

Kimia 400 cm of sodium hydroxide solution 0.5 mol dm 3 is used to neutralise 100 cm of hydrochloric
acid solution as shown in the reaction below.
NaOH(aq) + HCl(aq) - NaCl(aq) + H2O(1)
4
What is the concentration of the hydrochloric acid solution?
A 0.100 mol dm3
С 1.00 mol dm3
B 0.200 mol dm3
D 2.00 mol dm3

400 cm of sodium hydroxide solution 0.5 mol dm 3 is used to neutralise 100 cm of hydrochloric
acid solution as shown in the reaction below.
NaOH(aq) + HCl(aq) - NaCl(aq) + H2O(1)
4
What is the concentration of the hydrochloric acid solution?
A 0.100 mol dm3
С 1.00 mol dm3
B 0.200 mol dm3
D 2.00 mol dm3

Jawaban:

D. 2,00 mol/dm³

Penjelasan:

V NaOH = 400 cm³ = 0,4 dm³

M NaOH = 0,5 mol/dm³ or 0,5 M

V HCl = 100 cm³ = 0,1 dm³

Reaction:

NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)

Ask: concentration of HCl?

answer:

neutralise equation is:

Va x Ma x a = Vb x Mb x b

0,1 dm³ x Ma x 1 = 0,4 dm³ x 0,5 M x 1

0,1 dm³ x Ma = 0,2 mol

Ma = 0,2 mol / 0,1 dm³ = 2,00 M or 2,00 mol/dm³

nb:

cm³ = ml

dm³ = L

cmiiw ^^