When did Pangaea begin to break apart?

a. 20 million years ago

c. 250 million years ago

b. 100 million years ago

d. 2 billion years ago.

What is the purpose of cell wall

The formation of covalent bonds is ...

Lithium (Li) is higher than iron (Fe) on the activity series. What does this mean? A. Li will replace Fe in a combination reaction. B. Fe will replace Li in a single-replacement reaction. C. Li will replace Fe in a single-replacement reaction. D.

Sulfur trioxide, so3, is made industrially in enormous quantities by combining oxygen and sulfur dioxide, so2. what amount (moles) of so3 is represented by 3.00 kg of sulfur trioxide?

Which of these substances are compounds? How do you know? A. Salt (NaCl) B. Nitrogen (N) C. Helium (He) D. Water (H2O)

What kind of ions do a sodium atom and a chlorine atom become when a valence electron is transferred from one to the other?

NaOH and bleach have several characteristics in common. They include all BUT one of the characteristics listed.

What is the general form for the simplest type of acid-base reaction?

Which element has a larger atomic radius than sulfur? chlorine cadmium fluorine oxygen

Which of the following procedures is used when refining petroleum? Increase the temperature of the oil. Decrease the temperature of the oil. Increase the pressure of the oil. Decrease the pressure of the oil.