Which change occurs when an atom in an excited

state returns to the ground state?

(1) Energy is emitted.

(2) Energy is absorbed.

(3) The number of electrons decreases.

(4) The number of electrons increases.

An igneous rock with large crystals cooled 1. slowly 2. quickly 3. underwater 4. in a volcano

Sucralfate (molecular weight: 2087 g/mol) is a major component of Carafate®, which is prescribed for the treatment of gastrointestinal ulcers. The recommended dose for a duodenal ulcer is 1.0g taken orally in 10.

The negative of the common logarithm of the hydronium concentration of a solution is called ___.

A compound die will be used to blank and punch a large washer out of aluminum alloy sheet stock 3.2 mm thick. the outside diameter of the washer = 65 mm and the inside diameter = 30 mm.

A sample of a radioactive nuclide has a mass of 10 g. How many half lives must transpire until less than 21% of the original sample is present?

Which of the following lists the types of single substances? (Select only one answer) Group of answer choices elements and mixtures suspensions, solutions, and colloids elements, compounds, and mixtures elements and compounds

What is the average mass of a single silicon atom in grams?

Why is it wrong to assume that you are only "doing science" while you are doing experiments?

An ice cube is placed on a kitchen counter. Which best describes heat flow in this situation

When water is placed in a thin glass tube, it tends to climb up the walls of the tube. This effect is known as capillary action. What causes this capillary action? A. metallic bonding B. covalent bonding C. ionic bonding D. hydrogen bonding