As you move across a row from left to right in the period table, atomic numbers of the elements

a. decrease.

b. increase.

c. double.

d. stay the same.

Several lawmakers argue that constructing coal plants is a necessity. Which statements describe scientific evidence people can use to disagree with the lawmakers' claim? Check all that apply. Smog and other forms of air pollution are an issue.

Calculate the ph of a mixture made by adding 50.0 ml of 0.20 m hcl (aq) to 150.0 ml of water if the temperature of the mixture is 25.0 °c.

A neutral beryllium atom has four protons and five neutrons. How many electrons does it have?

Is tap water an element?

A voltaic cell is set up and a chemical reaction proceeds spontaneously. Which of the following will not occur in this reaction? a. The electrons will migrate through the wire b. The cations in the salt bridge will migrate to the anode half-cell c.

What mass of copper is consumed in the reaction with hydrochloric acid if 10.0 g of gas is collected?

How does the movement of molecules inside a solid block of iron change as the iron is heated? The molecules move faster. The molecules move slower. The molecules stop moving completely. The molecules move in the same way at all temperatures.

Read the following passage: The movement of tectonic plates buries a rock deep inside Earth. Intense heat and pressure change the mineral composition of the rock and transform it into Rock A.

What is a change which forms one or more new substances?

Which changes occur as a cadmium atom, Cd, becomes a cadmium ion, Cd2+? (1) The Cd atom gains two electrons and its radius decreases. (2) The Cd atom gains two electrons and its radius increases.