In the formula [tex]q=\frac{m}{MH}[/tex], where [tex]$q$[/tex] is the amount of substance, [tex]$m$[/tex] is mass, and [tex]$MH$[/tex] is molar mass, how would you solve for mass [tex]$m$[/tex]?
a. [tex]$m=MHq$[/tex]
b. [tex]$m=\frac{MH}{q}$[/tex]
c. [tex]$m=MH-q$[/tex]
d. [tex]$m=MH-q$[/tex]
Answer (2)
Start with the formula: q = M H m .
Multiply both sides by M H : q × M H = m .
Rewrite the equation: m = M H × q .
The solution for mass m is: m = M H q
Explanation
Understanding the Formula We are given the formula q = M H m , where q is the amount of substance, m is mass, and M H is molar mass. Our goal is to isolate m on one side of the equation.
Isolating m To solve for m , we need to eliminate the fraction by multiplying both sides of the equation by M H . This gives us: q M H = M H m M H
Final Equation Simplifying the right side of the equation, we get: q M H = m Thus, we have m = q M H , which is the same as m = M H q .
The Answer Therefore, the correct answer is m = M H q .
Examples
In chemistry, this formula is crucial for calculating the mass of a substance needed for an experiment, given the amount of substance (in moles) and the molar mass. For example, if you need 2 moles of NaCl (sodium chloride, molar mass approximately 58.44 g/mol), you can calculate the required mass as follows: m = ( 58.44 g / m o l ) × ( 2 m o l es ) = 116.88 g . This ensures accurate measurements and successful experimental outcomes. Understanding how to manipulate this formula is fundamental in stoichiometry and quantitative analysis.
To solve for mass m in the formula q = M H m , you multiply both sides by the molar mass M H to isolate m . This results in the equation m = M H q , which is option (a). Understanding this relationship is key in chemistry for calculating the mass of substances needed in reactions.
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