p. 76, #1, 3, 4, 5

p. 76, #1, 3, 4, 5
1.
Summarize the main ideas of Dalton’s atomic theory.
1.
Elements are made of tiny, unique particles called atoms. Atoms cannot be divided. Atoms of the same element are identical. Atoms of different elements can join to form molecules.
3. List the charge, mass, and location of each of the three subatomic particles found within atoms.
3.
The 3 subatomic particles are:
– Protons, which have a charge of +1, a mass of 1.67 * 10 -27 kg, and are in the nucleus;
– Neutrons, which have a charge of 0, a mass of a mass of 1.67 * 10 -27 kg, and are in the nucleus; and
– Electrons, which have a charge of -1, a mass of a mass of 9.11 * 10 -31 kg, and are outside the nucleus.

p. 76, #1, 3, 4, 5
4. Predict how many valence electrons a nitrogen atom has.
4. Nitrogen has 5 valence electrons. This is expected because nitrogen is in group 5.
5.
Explain why oxygen atoms are neutral.
5. Oxygen atoms are neutral because oxygen has 8 negatively charged electrons that balance out the charge of its 8 positively charged protons.