Which of the following elements have unstable electron shells?

A. Hydrogen (H)

B. Chlorine (Cl)

C. Calcium (Ca)

D. All of these

What are the superheavy elements and where are they located on the periodic table

Which of the following is a mixture? alcohol water mercury ink

Your old bike left out in the rain starts to rust. What coefficients fill in the blanks to balance the equation?

Which statement could Democritus and Aristotle agree on?

An oxygen atom has a mass of and a glass of water has a mass of. Use this information to answer the question below. Be sure your answers have the correct number of significant digits.

What jobs involve chesmistry

Think about a neutral magnesium atom. Then think of a magnesium ion with a 2+charge. How are these two alike? How are they different? Be sure to use the terms proton, neutron, and electron in your answer.

What subatomic particle is specifically responsible for combining the atoms together to form a new substance?

A chemist reported that 100 gallons of a gas were available in a laboratory. Which property of the gas did the chemist report?

Is the water density higher than the aluminum density