When the nucleus of an atom contains a constant number of protons but a variable number of neutrons, the atom is called a (n) ?

1) element

2) isotope

3) valence

4) dalton

What qualities make one theory "better" than another in the scientific community?

Which type of radiation do people try to protect themselves from by wearing protective clothing that is made of aluminum?

Describe the composition of the nucleus of an atom. A) It is composed of protons. B) It is composed of protons and neutrons. C) It is composed of protons and electrons. D) It is composed of protons, neutrons, and electrons.

Witch of the following causes earths plates to move continuously? A. Glacial deposits B. Earths magnetic field C. Convection in the Earth's mantle D. Radiation in the Earth's core

How to convert 5.58 deciliters to liters

A) If you weigh a hydrated compound before and after heating it. Do you expect the mass to be more or less than before heating? Explain why. b) How about if you weigh a bag of popcorn before and after heating it.

Define the term relative molecular mass

It took many of the metals several minutes to begin to react. Once the reaction was initiated, several of these metals continued to react quite vigorously.

What dose the smooth ER do

How many valence electrons are in each atom?