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Given that \$\\text{percentage concentration (w/v)}=\\dfrac{\\text{mass of solute (g)}}{\\text{volume of solvent (mL)}}\\times \\text{100},\$ which of the following is a valid equation for the mass of the solute (g)?

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$\\text{mass of solute (g)}=\\dfrac{\\text{percentage concentration (w/v)}}{\\text{100}}\\times \\text{volume of solvent (ml)}$

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$\\text{mass of solute (g)}=\\text{percentage concentration (w/v)}\\times \\text{volume of solvent (ml)}\\times {\\text{100}}$

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$\\text{mass of solute (g)}=\\text{percentage concentration (w/v)}\\times \\text{volume of solvent (ml)}$

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$\\text{mass of solute (g)}=\\dfrac{\\text{100}}{\\text{percentage concentration (w/v)}}\\times \\text{volume of solvent (ml)}$

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$\\text{mass of solute (g)}=\\dfrac{\\text{percentage concentration (w/v)}}{\\text{volume of solvent (ml)}}$

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$\\text{mass of solute (g)}=\\dfrac{\\text{volume of solvent (ml)}}{\\text{percentage concentration (w/v)}}$

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$\\text{mass of solute (g)}=\\dfrac{\\text{100}}{\\text{volume of solvent (ml)}}\\times {\\text{percentage concentration (w/v)}}$

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$\\text{mass of solute (g)}=\\dfrac{\\text{percentage concentration (w/v)}}{\\text{100}\\times \\text{volume of solvent (ml)}}$

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Given that \$\\text{percentage concentration (w/v)}=\\dfrac{\\text{mass of solute (g)}}{\\text{volume of solvent (mL)}}\\times \\text{100},\$

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to find an equation for 'mass of solute (g)', we need to get rid of all the other things on the right hand side of the equation (so that mass is by itself). To do this we divide both sides by 100 and multiply both sides by 'volume of solvent (mL)'.

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 $\\text{percentage concentration (w/v)}$ $=$ $\\dfrac{\\text{mass of solute (g)}}{\\text{volume of solvent (mL)}}\\times \\text{100}$ $\\dfrac{\\text{percentage concentration (w/v)}}{\\text{100}}$ $=$ $\\dfrac{\\text{mass of solute (g)}}{\\text{volume of solvent (mL)}}\\times \\dfrac{\\text{100}}{\\text{100}}$ $\\dfrac{\\text{percentage concentration (w/v)}}{\\text{100}}$ $=$ $\\dfrac{\\text{mass of solute (g)}}{\\text{volume of solvent (mL)}}$ $\\dfrac{\\text{percentage concentration (w/v)}}{\\text{100}}\\times \\text{volume of solvent (mL)}$ $=$ $\\dfrac{\\text{mass of solute (g)}}{\\text{volume of solvent (mL)}}\\times \\text{volume of solvent (mL)}$ $\\dfrac{\\text{percentage concentration (w/v)}}{\\text{100}}\\times \\text{volume of solvent (mL)}$ $=$ $\\text{mass of solute (g)}$
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https://en.wikipedia.org/wiki/Mass_concentration_(chemistry)#Usage_in_biology

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For Nursing and midwifery

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