Answer: 193 mg of theobromine are present in the sample.
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number of particles.
To calculate the moles, we use the equation:
1 mole of theobromine 
weigh = 180 g
of theobromine weigh = 
(1g=1000mg)
193 mg of theobromine are present in the sample.
(4 mol H2O) x (112 kJ / 3 mol H2O) = 149 kJ
<span>(14.5 g HCl) / (36.4611 g HCl/mol) x (112 kJ / 3 mol HCl) = 14.9 kJ </span>
<span>(475 kJ) / (181 kJ / 2 mol HgO) x (216.5894 g HgO/mol) = 1137 g HgO </span>
<span>(179 kJ) / (181 kJ / 1 mol O2) x (31.99886 g O2/mol) = 31.6 g O2 </span>
<span>(145 kJ) / (112 kJ / 3 mol Cl2) x (70.9064 g Cl2/mol) = 275 g Cl2 </span>
<span>(14.5 g S2Cl2) / (135.0360 g S2Cl2/mol) x (112 kJ / 1 mol S2Cl2) = 12.0 kJ </span>
<span>CaCO3 + 2 NH3 → CaCN2 + 3 H2O; ∆H = –90.0 kJ </span>
<span>(798 kJ) / (90.0 kJ / 2 mol HN3) x (17.03056 g NH3/mol) = 302 g NH3 </span>
<span>(19.7 g H2O) / (18.01532 g H2O/mol) x (90.0 kJ / 3 mol H2O) = 32.8 kJ</span>
Enzymes affect the rate of the reaction in both the forward and reverse directions; the reaction proceeds faster because less energy is required for molecules to react when they collide. Thus, the rate constant (k) increases. Figure 3: Lowering the Activation Energy of a Reaction by a Catalyst.
<em>Best of luck,</em>
<em>-Squeak</em>
Answer should be 20% so 1/5
First, we have to know that we can put [H+] instead of [H3O+]
so, according to the reaction equation:
by using ICE table:
H2O ↔ H+ + OH-
initial 0 0
change +X +X
Equ X X
when Kw = [H+] [OH-]
and when we have Kw = 2.4 x 10^-14
and when [H+] = [OH-] = X
∴ 2.4 x 10^-14 = X^2
∴ X = √(2.4 x 10^-14)
= 1.55 x 10^-7
∴[H+] = 1.55 x 10^-7
