What is the charge on he helium atom? Explain your reasoning. (A helium atom has two electrons, two protons, and two neutrons.)

If a radioactive material has a 10 year half-life, how much of a 100 g sample will be left after 30 years? A) 50 g B) 6.25 g C) 12.50 g D) 25 g

What is the word that means "these break food into pieces

Circle the chemical formula that is a simple sugar called sucrose. Explain how you know this C H O 12 22 11 C N NO 6 5 2

While exploring on your grandfathers farm, you find a layer of charcoal that might represent a campfire built by Native Americans. Explain how you could find the age of the charcoal layer?

4.5 * 1025 atoms of nickel equal how many moles?

When the Sun is in its maximum solar cycle, which of the following occurs? A. One CME is produced every five days B. There is an unpredictable amount of energy C. Up to three CMEs are created in one day D. Protons and neutrons accelerate

How many daughter cells are produced in meiosis?

Sodium chlorite - > sodium chloride + oxygen what type of chemical reaction is represented by this equation

The mixing of which pair of reactants will result in a precipitation reaction? the mixing of which pair of reactants will result in a precipitation reaction?

A balloon has 18.9 moles of hydrogen gas at a volume of 428 L. What would the volume of the gas be if the balloon had 14.0 moles of hydrogen gas left after 1 day?