Which of the answer choices accurately describes a trend that occurs when moving left to right across periods?

(Select all that apply.)

reactivity increases

atomic radius increases

atomic mass increases

valence electrons decrease

Which list of nuclear emissions is arranged in order from least penetrating power to the greatest penetrating power

Redox means reduction and oxidation. It can be defined by loss and gain of oxygen or by loss and gain of electrons. 1. Which definition is more useful?

The graph of the equation below is a circle what is the length of the radius of the circle (X-4) 2 + (y+12) 2=172

Is it correct to say that only one observable change accompanies a chemical change?

Why does air have weight? A. Because everything has weight B. The force of gravity acts on the air molecules' mass C. The pressure of the air molecules colliding with each other gives them weight D. Air fills its entire volume, producing weight

Which is the molar mass of Calcium?

Which statement best describes the nature of science? Science discoveries using the latest technology are the most valuable. Scientific theories and laws are based on beliefs and popular opinion.

vanadium has an atomic mass of 50.9415 amu. it has two common isotopes. one isotopes has a mass of 50.9440 amu and a relative abundance of 99.75%.

Which of the following could a magnet float over? A. A network solid B. A molecular solid C. A semiconductor D. A superconductor

What are genes a part of?