5.26 grams of Ca atoms to moles.

A scientist is observing onion cells and human cheek cells under a microscope.Which observation does she most likely make?

The onion cells have lysosomes, and the cheek cells do not.
The cheek cells have larger vacuoles than the onion cells.
The cheek cells have a nucleus, and the onion cells do not.
The onion cells have a cell wall, and the cheek cells do not.

Which of the following describes the tiny particles that make up matter? A. They are sometimes in motion
B. They are in constant motion
C. They are never in motion

D. They are sometimes not in motion.

The diagram below illustrates a chemical equation. Chemical equations can be used to model chemical changes and show how elements become rearranged during chemical reactions. Which statement about is chemical equation is true? A. Two compounds have reacted to produce one compound. B. Two elements have reacted to produce one element. C. One compound and one element have reacted to produce one compound. D. Two elements have reacted to produce one compound.

What happens when a pure substance undergoes a chemical change

Combustion reaction all follow a similar pattern, complete the work equation below Hydrocarbon + ... ---> Carbon... + ....

How does the temperature and pressure change inside the earth, moving downward from the crust to the core?A.
Both temperature and pressure decrease.

B.
Both temperature and pressure increase.

C.
Temperature increases, but pressure decreases.

D.
Temperature decreases, but pressure increases.