Ca(s)+2Hcl(aq) ------>CaCl2(s)+H2(g)
Using the titration formula, we know that:
(2.0 M)(volume of acid)=(3.0 M)(250 mL)
volume of acid = (3.0)(250)/(2.0) = 375 mL
Answer:
Explanation:
Given:
Ka of HClO2 = 1.1 × 10-2
Ka of HCHO2 = 1.8 × 10-4
Ka of HCN = 4.9 × 10-10
Ka of HNO2 = 4.6 × 10-4
Ka of HF = 3.5 × 10-4
All at a concentration of 0.1 M
A.
HA --> H+ + A-
Ka = [H+] × [A-]/[HA]
[H+] = [A-] = x
[HClO2] = 0.1 M
HClO2 --> ClO2^- + H+
1.1 × 10-2 = x^2/0.1
x = sqrt(1.1 × 10^-3
= 0.033 M
pH = -log[H+]
= 1.48
B.
HA --> H+ + A-
Ka = [H+] × [A-]/[HA]
[H+] = [A-] = x
[HCHO2] = 0.1 M
HCHO2 --> CHO2^- + H+
1.8 × 10-4 = x^2/0.1
x = sqrt(1.8 × 10^-5)
= 0.0042 M
pH = -log[H+]
= 2.37
C.
HA --> H+ + A-
Ka = [H+] × [A-]/[HA]
[H+] = [A-] = x
[HCN] = 0.1 M
HCN --> CN- + H+
4.9 × 10-10 = x^2/0.1
x = sqrt(4.9 × 10-11)
= 0.000007 M
pH = -log[H+]
= 5.16
D.
HA --> H+ + A-
Ka = [H+] × [A-]/[HA]
[H+] = [A-] = x
[HNO2] = 0.1 M
HNO2 --> NO2^- + H+
4.6 × 10-4 = x^2/0.1
x = sqrt(4.6 × 10-5)
= 0.0068 M
pH = -log[H+]
= 2.17
E.
HA --> H+ + A-
Ka = [H+] × [A-]/[HA]
[H+] = [A-] = x
[HF] = 0.1 M
HF --> F- + H+
3.5 × 10-4 = x^2/0.1
x = sqrt(3.5 × 10-5)
= 0.0059 M
pH = -log[H+]
= 2.23
a) pH = 1.48
b) pH = 2.37
c) pH = 5.16
d) pH = 2.17
e) pH = 2.33
HCN is most basic because;
smallest Ka
Highest pH value = 5.16
False
Explanation:
A plant will die after being exposed to poison does not represent a physical change. A physical change is one that alters the physical state of matter and leads to no formation of new substances.
- The plant dies due to chemical changes in its structure.
- The poison will react with the chemicals in the system of the plant to produce new harmful ones.
- In a chemical change, new kind of substance forms in the plant and the change is irreversible.
Learn more:
Chemical change brainly.com/question/9388643
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Answer : -4.65 °C
Explanation : On solving the sum w.r.t to water as the aqueous solvent in solution;
(101.28°C - 100°C) / (0.512 c/m) = 2.5 m,
Now, 2.5 m X (1.86 °C/m) = 4.65 °C which will be the change in temperature of the solution in °C;
To find the freezing point we have to get it subtracted by 0°C
0°C - 4.65°C = -4.65°C
