Which of the following is an example of a quantitative observation?

Convert 0.000789 to scientific notation with three significant figures.

If a reaction requires 2 moles of a substance, how many molecules are needed? (Use Avogadro's number: 6.022 x 10²³)

A scientist needs to express a measurement of 0.0000000075 meters using a metric prefix. Which is the most appropriate expression?

How many significant figures are in the number 0.0200?

If you multiply 2.5 by 3.42, how many significant figures should the result have?

Calculate the following expression and express the answer with the correct number of significant figures: (6.022 x 10²³) x (3.0 / 2.5) + 1.2.

A car's fuel efficiency is rated at 25 miles per gallon. If 1 gallon equals 3.785 liters, how many kilometers per liter does the car achieve? (1 mile = 1.60934 km)

Convert 45.0 grams to ounces using the conversion factor 1 ounce = 28.3495 grams. What is the result with the correct significant figures?

Convert a density of 1.5 g/cm³ to kg/m³.

A metal object is submerged in a graduated cylinder, causing the water level to rise from 30.0 mL to 36.5 mL. If another object is added, and the water level rises to 42.0 mL, what is the volume of the second object?

Which of the following best describes a compound?

Why is diamond considered one of the hardest materials?

Which phase change involves a substance going directly from a solid to a gas?

How are reactants transformed into products during a chemical reaction?

A cylinder has a radius of 2 cm and a height of 5 cm. What is its volume?

Which of the following best defines thermal energy?

In a closed system, 10 grams of A reacts with 15 grams of B to form 5 grams of C and an unknown amount of D. What is the mass of D?

How many joules are in 2 kilowatt hours?

A system absorbs 50 J of heat and does 20 J of work on its surroundings. What is the change in internal energy?

In an energy diagram for an endothermic reaction, how do the energy levels of reactants and products compare?

If 400 J of heat is applied to 3 moles of a substance, resulting in a temperature change of 10°C, what is the molar heat capacity?