Thorium-229 is a highly radioactive isotope. Use the chart to determine the half-life of Th-229. A) 7,340 years B) 8 years C) 16 years D) 22,020 years

Which of the following causes an increase in the atomic number? A) alpha emission B) beta emission C) gamma emission D) none of the above

A block of metal is on a table. Which must be true for thermal energy to flow from the table to the metal? A. Both the table and the metal must be cooler than surrounding air. B. The metal must be cooler than the air. C.

Why will oil and water never mix second law of thermodynamics?

Which of the following statements holds true for chemical change? A) in a chemical change, no new substance is formed B) in a chemical change, a substance changes its phase C) in a chemical change, the molecular structure of a substance changes D)

A sulfur ion has 16 protons and 18 electrons. Find the net charge

When does a spring tide take place? At the beginning of spring Only during the spring season Only after spring is over At any time

The highest cloud are known as

What is the mass of 4.85 X 10^22 atoms of iron (Fe) ?

If element x has 95 protons how many electrons does it have

Which of the following when dissolved in deionized water would make a good conducting solution? a) methanolb) sugarc) baking soda