Which scientist discovered that other galaxies and stars were moving away from us at speeds proportional to how far they were away?

When carbon undergoes sp2 hybridization it forms

Hard water contains calcium and magnesium, which undergo oxidation and clog water pipes. Which statement best describes this change as a chemical change? A. Calcium and magnesium dissolve in water. B.

A nail is attracted to a magnet. What does this tell you about the nail? O A. It is harder than the magnet. O B. It is a poor thermal conductor. O C. It contains iron. O D. It is a good electrical conductor.

What is an emperical formula?

The table below shows the electronegativity values of various elements on the periodic table. electronegativities which pair of atoms would form a covalent bond?

Why does the effective nuclear charge increase across a row of the periodic table?

Iodine-131 decays to form xenon-131. the half-life of this reaction is 8.07 days. from a 200-g sample of iodine-131, how much of the sample is xenon-131 after 16.14 days?

Complete the following statement by checking all that apply Creativity allows scientists to develop multiple approaches to solving problems. adapt to changes in scientific knowledge. look at old problems in new ways.

The atomic weight of hydrogen is 1.00794. a. True b. False

Describe What kind of ions do metals form? What kind of ions do nonmetals form?