The mole is a really helpful way to count really small things. Are there other methods we use to help us count? Do we have a number that helps us group really large things? Give some examples (not listed in the video) of how we group items on a daily basis.

Put these processes of the water cycle in the correct order, starting at the point where the water is in the lake: 1. water evaporates into the atmosphere 2. rain, snow, or other precipitation falls 3. water collects into larger bodies of water 4. water vapor condenses into liquid water

Which statement best describes the relationship between period and frequency of light waves? a) in wave b the period increases and the frequency decreases from wave a. b) in wave a the period increases and the frequency decreases from wave b. c) in wave b the period is shorter and the frequency is greater than in wave a. d) in wave a the period is shorter and the frequency is greater than in wave b.

Read the chemical equation. 2c2h2 + 5o2 → 4co2 + 2h2o which of the following statements would be correct if one mole of c2h2 was used in this reaction? one mole of oxygen was used in this reaction. five moles of oxygen were used in this reaction. four moles of carbon dioxide were produced from this reaction. two moles of carbon dioxide were produced from this reaction.