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 %
A, The moon pulls on the earth making the tides rise and fall
The pH unit has 10x as many hydrogens ions as the unit above.
Ex: A pH of 5 would have 10x more hydrogen ions than a pH of 6
and 100x more than if it had a pH of 7.
With a pH of 9 and 3, this is equivalent to 10⁶
So your answer should be:
1,000,000
Answer:
4) a mixture.....................
Answer: The given statement is TRUE.
Explanation:
An equilibrium reaction is one in which rate of forward reaction is equal to the rate of backward reaction.
Equilibrium constant is defined as the ratio of the product of the concentration of products to the product of the concentration of reactants each raised to their stochiometric coefficient.
For example for the given equilibrium reaction;

![K_{eq}=\frac{[H_2]^2[O_2]}{[H_2O]^2}](https://tex.z-dn.net/?f=K_%7Beq%7D%3D%5Cfrac%7B%5BH_2%5D%5E2%5BO_2%5D%7D%7B%5BH_2O%5D%5E2%7D)
Thus the given statement that in calculating the equilibrium constant for a reaction, the coefficients of the chemical equation are used as exponents for the factors in the equilibrium expression is True.