Question

. Which particles have almost the same mass?
(1 point)proton and electron

proton and neutron

electron and neutron

all three particles


2. Which item best represents Thomson’s mental image of an atom?
(1 point)a sponge

a chocolate-chip cookie

a frisbee

a potato chip


3. A transmutation involving the release of alpha particles that produces atoms with an atomic number has ____.
(1 point)decreased by two

increased by two

decreased by one

increased by one




Figure 15-1

4. When Mendeleyev published his periodic table, there were some spaces