A single atom of an element has 21 neutrons, 20 electrons, and 20 protons. Which element is it?

K

Zr

Ca

Sc

During which stage of the cell cycle dies the cell condense chromosomes and break down the nuclear envelope

Match the Greek or English symbol to the atomic subunits. 1. β neutron 2. π gamma 3. ρ meson 4. η alpha 5. α proton 6. γ beta

Use the following chemicals. ethanol, hexane, butanone, water, benzene, diethyl ether, ethyl acetate, acetone 4. Rank the solvents based on polarity, smallest to largest.

Which element do you expect to be most like magnesium? Why? a.) potassium b.) silver c.) bromine d.) calcium e.) lead

What is the mass of sodium in 3 moles of sodium chloride

If 100 grams citric acid react with 100 g baking soda how many grams of carbon dioxide?

What state of matter undergoes changes in volume most easily? a. solidb. liquidc. gasd. frozen

What was the result of the atomic theory?

Explain mitosis and meiosis in your own words.

What device changes mechanical energy into electrical energy? Question 4 options: transformer generator copper wire light switch