The SI unit for the amount of substance present is the mole.
The mole is defined as the amount of substance that has the same amount of particles as there are atoms in 12 grams of carbon-12. Mathematically, the moles of a substance may be computed using:
moles present = mass of substance / molecular mass of substance
<span>a. Tall prarie grass burns after being struck by lightning.</span>
Answer:
See Explanation
Explanation:
The question is incomplete; as the mixtures are not given.
However, I'll give a general explanation on how to go about it and I'll also give an example.
The percentage of a component in a mixture is calculated as:

Where
E = Amount of element/component
T = Amount of all elements/components
Take for instance:
In 
The amount of all elements is: (i.e formula mass of
)



The amount of calcium is: (i.e formula mass of calcium)



So, the percentage component of calcium is:




The amount of hydrogen is:



So, the percentage component of hydrogen is:




Similarly, for oxygen:
The amount of oxygen is:



So, the percentage component of oxygen is:




<span>There
are a number of ways to express concentration of a solution. This includes
molarity. Molarity is expressed as the number of moles of solute per volume of
the solution. So, we calculate as follows:
Molarity = 15.9 g BaCl2 ( 1 mol / 208.23 g ) / .375 L = 0.204 mol / L</span>
<span>the balanced equation for the reaction is as follows
Na</span>₂<span>SO</span>₄<span> + BaCl</span>₂<span> ----> 2NaCl + BaSO</span>₄
<span>stoichiometry of Na</span>₂<span>SO</span>₄<span> to BaCl</span>₂<span> is 1:1
first we need to find out which the limiting reactant is
limiting reactant is fully used up in the reaction.
number of Na2So4 moles - 0.5 mol number of BaCl2 moles - 60 g / 208 g/mol = 0.288 mol
since molar ratio is 1:1 equal number of moles of both reactants should react with each other
therefore BaCl2 is the limiting reactant and Na2SO4 is in excess. amount of product formed depends on number of limiting reactant present.
stoichiometry of BaCl</span>₂<span> to BaSO</span>₄<span> is 1:1.
therefore number of BaSO4 moles formed - 0.288 mol</span>