Day 1 Review

Which of these best describes the basis on which new scientific ideas are accepted or rejected?

• Popular support

• Historical support

• Compelling evidence

• Moral and ethical beliefs

Students want to separate and compare the components of black ink and green ink. Which technique is the best for the students to use?

• Chromatography

• Decanting

• Filtration

• Evaporation

An example of a chemical property is-

• mass of a substance per unit volume

• ability to dissolve in solution

• point where solid becomes liquid

• tendency to undergo oxidation

To determine if a reaction is exothermic, a student should use a-

• pH probe

• motion sensor

• pressure sensor

• thermometer

If a sample has a mass of 1.25 x 10² g and a volume of 51 mL, what is its density?

• 0.00025 g/mL

• 0.01252 g/mL

• 2.5 g/mL

• 250 g/mL

When 1 g of sodium chloride (NaCl) is placed in 100 g of water, a solution results. Once the solution is prepared, water is not considered what part of the solution?

• Solid

• Liquid

• Solute

• Solvent

hen 80 g of sodium hydroxide (NaOH), are dissolved in enough water to make 500 mL of solution, the molarity of the solution is-

• 1 M

• 2 M

• 4 M

• 8 M

Which of the following solutions will have the greatest concentration?

• 2 moles of solute dissolved in 1 liter of solution

• 0.3 moles of solute dissolved in 0.6 liter of solution

• 2 moles of solute dissolved in 10 liters of solution

• 0.1 mole of solute dissolved in 0.5 liter of solution

What is the molar mass of beryllium oxide (BeO)?

• 12 g/mol

• 13 g/mol

• 24 g/mol

• 25 g/mol

A 0.67 L solution of ammonium sulfate, (NH₄)₂SO₄, contains 0.81 moles of the solute. What is the approximate molarity of the solution?

• 0.54 M

• 0.83 M

• 1.2 M

• 1.5 M