Answer:
19 protons, 20 neutrons and 18 electrons.
Explanation:
The atomic number gives the number of protons 19
p
=
19
The atomic mass is the sum of the protons and neutrons
p
+
n
=
39
p
=
19
put p into the equation and solve for n the neutrons.
19
+
n
=
39
Subtract 19 from both sides
19
−
19
+
n
=
39
−
19
n
=
20
The number of electrons equals the number of protons in a neutral atom. The positive charge equals the negative charge. The negative charge is the number of electrons. This ion has a charge of +1. So solve for the negative charge.
−
19
+
1
=
−
18
The negative charge is -18 so
e
=
18
Answer:
about 0.7 g/mL
Explanation:
Density = mass ÷ volume
D = 5.29 g / (12.6 mL - 5.00 mL)
D = 5.29 g / 7.6 mL
D = 0.696052.... g/mL
D = about 0.7 g/mL
Answer:
3'' one is correct answer
Explanation:
in mutualism, organisms of different species benefit from cooperation
Answer:
D. Kinetic energy and is present in all states of matter.
Step-by-step explanation:
According to <em>Kinetic Molecular Theory,</em> all particles of matter are in constant, random motion.
The energy of this motion is kinetic energy.
It is A; <span>[He] 2s</span>²<span> 2p</span>² is another way to put it