Is photosynthesis, in which light energy is captured by plants to make sugar from carbon dioxide and water, a physical change or a chemical change? Explain your answer.

Write the electron configuration of germanium whose atomic number is 32.

Write on a separate sheet of paper the letter of the correct answer. Which of the following statements about compounds is true? F. A compound contains only one element. G. A compound can be classified as either heterogeneous or homogeneous. H. A compound has a defined ratio by mass of the elements that it contains. I. A compound varies in chemical composition depending on the sample size.

Calculate the number of atoms present in each of the following: a. 2 mol Fe, b. 40.1 g Ca, which has an atomic mass, of 40.08 amu, c. 4.5 mol of boron-11.

What element has this electron configuration? 1s2 2s2 2p6 3s2 3p4

Your friend mentions that she eats only natural foods because she wants her food to be free of chemicals.What is wrong with this reasoning?

What units are used to express mass and weight?

How are atoms and molecules related?

Use the following terms to create a concept map: volume, density, matter, physical property, and mass.

Make a poster showing the types of product warning labels that are found on products in your home.

Your teacher will provide you with a sample of a metallic element. Determine its density. Check references that list the density of metals to identify the sample that you analyzed.

A student leaves an uncapped watercolor marker on an open notebook. Later, the student discovers the leaking marker has produced a rainbow of colors on the top page. a. Is this an example of a physical change or a chemical change? Explain your answer. b. Should the ink be classified as an element, a compound, or a mixture? Explain your answer.

Classify the following materials as solid, liquid, or gas at room temperature: milk, helium, granite, oxygen, steel, and gasoline.

Which of the following is an element? A. $BaCl_2$, B. $CO$, C. $He$, D. $NaOH$.