{"id":36046,"date":"2025-06-25T01:55:03","date_gmt":"2025-06-25T01:55:03","guid":{"rendered":"https:\/\/gaviki.com\/blog\/?p=36046"},"modified":"2025-06-25T01:55:04","modified_gmt":"2025-06-25T01:55:04","slug":"50-g-of-nano3-was-dissolved-in-1250-ml-of-water","status":"publish","type":"post","link":"https:\/\/gaviki.com\/blog\/50-g-of-nano3-was-dissolved-in-1250-ml-of-water\/","title":{"rendered":"50 g of NaNO3 was dissolved in 1250 mL of water."},"content":{"rendered":"\n

50 g of NaNO3 was dissolved in 1250 mL of water. What is the molality of the solution? (Molar mass of NaNO3 85 g\/mol)<\/p>\n\n\n\n

The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n

Correct Answer: 0.47 mol\/kg<\/strong><\/p>\n\n\n\n

Explanation:<\/strong><\/h3>\n\n\n\n

To calculate the molality<\/strong> of a solution, we use the formula:Molality (m)=moles of solutemass of solvent in kg\\text{Molality (m)} = \\frac{\\text{moles of solute}}{\\text{mass of solvent in kg}}Molality (m)=mass of solvent in kgmoles of solute\u200b<\/p>\n\n\n\n

\n\n\n\n

Step 1: Calculate the moles of NaNO\u2083<\/strong><\/h3>\n\n\n\n

You are given:<\/p>\n\n\n\n

    \n
  • Mass of NaNO\u2083 = 50 g<\/li>\n\n\n\n
  • Molar mass of NaNO\u2083 = 85 g\/mol<\/li>\n<\/ul>\n\n\n\n

    Now calculate the number of moles:Moles of NaNO\u2083=50 g85 g\/mol\u22480.588 mol\\text{Moles of NaNO\u2083} = \\frac{50 \\text{ g}}{85 \\text{ g\/mol}} \\approx 0.588 \\text{ mol}Moles of NaNO\u2083=85 g\/mol50 g\u200b\u22480.588 mol<\/p>\n\n\n\n

    \n\n\n\n

    Step 2: Convert volume of water to mass of solvent<\/strong><\/h3>\n\n\n\n

    You are given 1250 mL of water. Since the density of water is approximately 1.00 g\/mL, this means:Mass of water=1250 mL\u00d71.00 g\/mL=1250 g\\text{Mass of water} = 1250 \\text{ mL} \\times 1.00 \\text{ g\/mL} = 1250 \\text{ g}Mass of water=1250 mL\u00d71.00 g\/mL=1250 g<\/p>\n\n\n\n

    Convert grams to kilograms:1250 g=1.250 kg1250 \\text{ g} = 1.250 \\text{ kg}1250 g=1.250 kg<\/p>\n\n\n\n

    \n\n\n\n

    Step 3: Calculate molality<\/strong><\/h3>\n\n\n\n

    Now use the molality formula:Molality=0.588 mol1.250 kg\u22480.47 mol\/kg\\text{Molality} = \\frac{0.588 \\text{ mol}}{1.250 \\text{ kg}} \\approx 0.47 \\text{ mol\/kg}Molality=1.250 kg0.588 mol\u200b\u22480.47 mol\/kg<\/p>\n\n\n\n

    \n\n\n\n

    Final Answer:<\/strong><\/h3>\n\n\n\n

    The molality of the solution is approximately 0.47 mol\/kg.<\/strong><\/p>\n\n\n\n

    \n\n\n\n

    Why this matters:<\/strong><\/h3>\n\n\n\n

    Molality is a concentration unit based on the mass of the solvent, not the volume of the solution. This makes it particularly useful when dealing with temperature-dependent properties like boiling point elevation and freezing point depression, because mass does not change with temperature, while volume can expand or contract. It is especially important in colligative property calculations in physical chemistry.<\/p>\n\n\n\n

    \"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"

    50 g of NaNO3 was dissolved in 1250 mL of water. What is the molality of the solution? (Molar mass of NaNO3 85 g\/mol) The Correct Answer and Explanation is: Correct Answer: 0.47 mol\/kg Explanation: To calculate the molality of a solution, we use the formula:Molality (m)=moles of solutemass of solvent in kg\\text{Molality (m)} = \\frac{\\text{moles of solute}}{\\text{mass of solvent in kg}}Molality (m)=mass of solvent in kgmoles of solute\u200b […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-36046","post","type-post","status-publish","format-standard","hentry","category-quiz-questions"],"_links":{"self":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/36046","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/comments?post=36046"}],"version-history":[{"count":1,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/36046\/revisions"}],"predecessor-version":[{"id":36048,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/36046\/revisions\/36048"}],"wp:attachment":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/media?parent=36046"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/categories?post=36046"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/tags?post=36046"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}