2. OBJECTIVES
INFER THAT OBJECTS MAY ATTRACT OR
REPEL EACH OTHER
DEDUCE THAT NEUTRAL OBJECTS
CONTAIN POSITIVE AND NEGATIVE
CHARGES
3. ATOMS
is regarded as the smallest, basic unit of matter. Even if
it is the basic unit of matter, it is still composed of
parts.
Atoms contain particles with positive and negative
charges. The proton carries a positive charge (+1).
The electron carries a negative charge (-1). Atoms,
in their most stable state
are neutral with an equal number of protons and
electrons.
4. instrument is used to
measure charges and the
measured units may be
expressed in coulombs.
For the electrons, the
actual charge is -1.602
x 10-19 coulombs;
while for the protons
it is +1.602 x 10-19
coulombs.
6. ACTIVITY 2
1. compare the masses of the
subatomic particles using
different ways of visual
representation
2.infer which subatomic particle
contributes to the mass of the
atom
7. Q1. Which subatomic particle is the lightest?
Electrons
Q2. Which subatomic particle is the heaviest?
Neutrons
8. Q3. Which subatomic particles have almost the
same mass?
Neutrons and Protons
Q4.How does the mass of the neutron compare with the
mass of the proton? Using circles to represent the particles
show the comparison by drawing a seesaw with the particles
on it.
The masses of the protons and neutrons are almost the same
9. Q5. How many electrons should be placed on one side of the seesaw to
balance it if the other side has 1 proton on it, like the one shown below?
Write the number on the space provided in the illustration below.
1836 electrons
Computation:
no. of electrons (mass of 1 electron) = mass of 1 proton
no. of electrons (9.109 x 10-28 grams) = 1.672 x 10-24 grams
no. of electrons = 1.672 x 10-24 grams / 9.109 x 10-28 grams
no. of electrons = 1836
10. Q6. Which subatomic particle/s make/s up most
of the mass of the atom?
Neutrons and protons
11. The massive part of the atom, then, comes
from the masses of the protons and neutrons.
Collectively, the protons and neutrons are
called nucleons. The nucleons, tightly packed
together, form the nucleus in the center of the
atom. Thus, most of the mass of the atom is
contained in its nucleus.
