How many electron does a neutral atom of calcium have

How does a electromagnet work

Which sphere includes rocks and minerals? A. atmosphere B. biosphere C. geosphere D. hydrosphere

Obi is trying to determine if a powdery, solid substance is an element or a compound. After recording some observations, he strongly heats a sample of the solid over a burner flame.

A sample of gas contains 6.25 * 10-3 mol in a 500.0 mL flask at 265°C. What is the pressure of the gas in kilopascals? Which variables are given?

Which of the following is true about mixtures and compounds? A. A mixture contains different substances that are not chemically combined with one another. OB. A compound forms when different substances chemically combine to form a new substance. C.

Which statements correctly describe water boiling in a pot? Air bubbles from the atmosphere are being absorbed. The water's internal kinetic energy is increasing. The water is gaining internal potential energy. The water's temperature is increasing.

Biofuel is any fuel that is produced from living or once living matter in a short period of time, days, weeks, or even months.

How are revolution and year related

Read the scientific question below. "Does sunlight make plants live?" What is a likely hypothesis for the question?

A chemist is using a solution of HNO3 that has a pH of 3.75. What is [H+] for the solution?