Molarity = Moles/Liter
Use the molecular atomic mass of NaCl to convert from grams to moles.
Molecular mass of NaCl is the sum of its atomic masses. Look at the periodic table to find these. Na is 23 g/mol and Cl is 35.5 g/mol ,
so NaCl = 23 + 35.5 = 58.5 g/mol
multiply to cancel out grams
76 g NaCl * (1mol / 58.5 g NaCl) = 1.3 mol NaCl
over 1 Liter is just 1.3 M NaCl
Answer:
She can add 380 g of salt to 1 L of hot water (75 °C) and stir until all the salt dissolves. Then, she can carefully cool the solution to room temperature.
Explanation:
A supersaturated solution contains more salt than it can normally hold at a given temperature.
A saturated solution at 25 °C contains 360 g of salt per litre, and water at 70 °C can hold more salt.
Yasmin can dissolve 380 g of salt in 1 L of water at 70 °C. Then she can carefully cool the solution to 25 °C, and she will have a supersaturated solution.
B and D are wrong. The most salt that will dissolve at 25 °C is 360 g. She will have a saturated solution.
C is wrong. Only 356 g of salt will dissolve at 5 °C, so that's what Yasmin will have in her solution at 25 °C. She will have a dilute solution.
Answer:
Yes, that is correctly balanced. 2 H2 + 1 O2 = 2 H2O is already balanced.
Explanation:
If you count up the number of hydrogen atoms and oxygen atoms on each side, you will see that they are equal:
2 H2 + 1 O2 (4 hydrogen and 2 oxygen) = 2 H2O (4 hydrogen and 2 oxygen).
Answer:
I believe the correct answer is D.
Explanation:
You are breathing in dinitrogen and dioxygen. You exhale dinitrogen and carbon dioxide. And the atmosphere contains traces of other gases. You drink water. You have a wash with water, and soap. You eat carbohydrates and proteins. You ride to work on a vehicle powered by hydrocarbons, which spits out carbon dioxide exhaust fumes, and also some nitrogen oxides. And so your exposure to chemicals is pervasive, and unavoidable.
