Answer:
A. The accepted model of the atom was changed.
Explanation:
Thomson described an atom that has the protons uniformly distributed within a circular atom with the electrons embedded . However, it cannot explain the emission of electrons from the surfaces of metals like photoelectric emission. it does not explain how the particle of the atom contribute significantly to the entire mass of an atom
Answer:
5.36 grams the mass in grams of zinc nitrate the chemist has added to the flask.
Explanation:

Moles of zinc nitrate = n
Volume of the solution = 135.0 mL = 0.1350 L
Molarity of the solution = 0.21 M


Mass of 0.02835 moles of zinc nitrate:
0.02835 mol × 189 g/mol = 5.358 g ≈ 5.36 g
5.36 grams the mass in grams of zinc nitrate the chemist has added to the flask.
Alpha and Beta particles can be stopped by our skin. Gamma particles cannot be stopped by our skin.
Explanation:
The reactants are Aluminium and Copper chloride.
The products are Copper and Aluminium chloride.
The volume of a gas that its pressure increase to 3.4 atm is calculated as follows
By use of boyles law that is P1V1=P2V2
V1=4.0 L
P1=1.1 atm
P2=3.4 atm
V2= P1V1/P2
(1.1 atm x 4.0 L)/3.4 atm= 1.29 L