Answer: 27.27%
Mass percentage of carbon in carbon dioxide is 4412×100=27. 27%.
The % yield if 200g of chlorine react with excess Potassium bromide to produce 410g of bromine is calculated as below
% yield = actual yield/theoretical yield x100
the actual yield = 410 grams
calculate the theoretical yield
by first calculate the moles of chlorine used
mole= mass/molar mass
molar mass of Cl2 = 35.5 x2= 71 g/mol
moles= 200g/71g/mol = 2.82 moles
cl2 +2 KBr = 2KCl +Br2
by use of mole ratio between Cl2 to Br2 which is 1:1 the moles of Br2 is also = 2.82 moles
theoretical mass = moles x molar mass
molar mass of Br2= 79.9 x2= 159.8 g/mol
moles= 2.82g x 159.8 g/mol = 450.64 grams
% yield is therefore = 410g/450.64 x100 = 90.98 %
<span>As the number of electrons added to the same principal energy level increases, atomic size generally A. increases.
</span>
<span>Because
as you add energy levels, the electrons are drawn to the nucleus of the atoms giving them a
lesser charge. Thus its atomic size also increases. </span>
Answer:
19.5
Explanation: using dalton law pt=p1+p2+p3...
the total pressure is 37.9 so to get pressure of gas b subtract pressure of gas a from total pressure.37.9-18.4 gas b equals 19.5
Nitrous acid<span> dissociates as follows:
</span>
HNO₂(s) ⇄ H⁺(aq) + NO₂⁻(aq)
According to the equation, an acid constant has the following form:
Ka = [H⁺] × [NO₂⁻ ] / [HNO₂]
From pH, we can calculate the concentration of H⁺ and NO₂⁻:
[H⁺] = 10^-pH = 10^-2.63 = 0.00234 M = [NO₂⁻]
Now, the acid constant can be calculated:
Ka = 0.00234 x 0.00234 / 0.015 = 3.66 x 10⁻⁴
And finally,
pKa = -log Ka = 3.44
