15. D is correct, exothermic reactions release heat
I am not sure about 16
the unnamed spacecraft which travels to Mars, will have the greatest weight on the Earth.
Answer:
1x10^–9 M
Explanation:
From the question given,
Concentration of hydronium ion, [H3O+] = 1x10^-5 M.
Concentration of Hydroxide ion, [OH-] =..?
The concentration of the hydroxide ion, [OH-] can be obtained as follow:
[H3O+] x [OH-] = 1x10^–14
1x10^-5 M x [OH-] = 1x10^–14
Divide both side by 1x10^-5
[OH-] = 1x10^–14 / 1x10^-5
[OH-] = 1x10^–9 M
Hey there!
<span>Atomic Masses :
</span>
H = <span>1.00794 a.m.u
N = </span><span>14.0067 a.m.u
O = </span><span>15.9994 a.m.u
Therefore:
HNO3 = </span>1.00794 + 14.0067 + ( 15.9994 * 3 ) => <span>63.0128 g/mol</span>