3. The Macy's Thanksgiving Day parade is famous for its giant balloons. The Cheerios Bee balloon holds 4.044x10'L of He. If the density of He is 0.000178 kg/L, what is the mass, in kg, of the hellum in that balloon? Work: Calculated # sig figs Final Answer with Units

1. a)c-14 has two more protons

2. d)they have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.

3. c) iron and nickel.

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.