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 type of chemical reaction is 4 Fe + 302 → 2Fe20; ? O single-displacement decomposition synthesis double-displacement

17. A gas tank holds 2785 L of propane, C3H8, at 830. mm Hg. What is the volume of the propane at standard pressure?

Which term describes the degree to which an element attracts electrons?

Which material is most dense air ice plastic or gold

Indicate how many significant figures in the following number 1.080

Which earth cycle does the suns energy drive

How many moles are in 10 grams of CaCl2?

Which is the correct formula for phosphorus pentachloride? PCl4 because a subscript of 4 indicates four Cl atoms PCl5 because a subscript of 5 indicates five Cl atoms P5Cl because a subscript of 5 indicates five P atoms P5Cl3 because a subscript of

Why are the elements in groups 3 to 12 often used to make dyes?

What is not needed for corrosion of metals? a. oxygen c. water b. ions d. sunlight