Answer:
An atom is made of up subatomic particles called protons, neutrons and electrons. The center of an atom is called the nucleus and is where the protons and neutrons are held while electrons orbit the nucleus in orbital shells. A electron has a negative charge, a proton has a positive charge, and a neutron has no charge (neutral).
The atomic number of a atom is the total amount of the atom's protons. In a neutral atom (Not an ion), the amount of electrons is the same as the protons. Therefore, the atomic number also tells the amount of electrons in the atom.
A ion is a negatively or positively charged particle due to the giving or taking of electrons with one or more atoms (Called an ionic bond). An atom that gives away electrons becomes positively charge because that atom now has more protons than neutrons. An atom that takes an electron becomes negatively charge because that atom now has more electrons than protons.
Atomic Mass is the sum of an atom proton and neutrons. To determine how many neutron an atom has, subtract the atomic mass from the atomic number. Electrons do not play a part in atomic mass as their mass is 1/1,836 of a proton's mass.
A isotope is two or more forms of the same element that contain equal amounts of protons but different amount of neutrons.
<span>Argon and chlorine are both gases at room temperature because they are non-metals.</span>
Answer:
<u><em>The correct option is C) the moon takes the same time to rotate and revolve.</em></u>
Explanation:
Scientific experiments have concluded that it takes approximately 23 days for the moon to rotate and also it takes the same duration for the moon to revolve around the Earth. Due to this consistency, the moon appears to be still.
<em>Such synchronization results in the same face of the moon to be directed towards the Earth. Hence, the same craters of the moon will be observed by the scientist every day.</em>
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Other options, like option D, is not correct because there will be craters on the other side of the moon too. But as we see the same side of the moon, hence we cannot see the craters present on the other side of the moon.
Answer:
Option C is correct.
t = 1.95 billion years.
Explanation:
Radioactive decay follows a first order reaction kinetics.
On solving the dynamic equation (the differential equation), this is obtained
C(t) = C₀ e⁻ᵏᵗ
C(t) = amount of radioactive material remaining after time t = 37.5%
C₀ = Initial amount of radioactive material = 100%
t = time that has passed = ?
k = decay constant.
For a first order reaction, the decay constant is related to the half life through the relation
k = (In 2)/T
T = half life = 1.38 billion years
k = (In 2)/1.38
k = 0.5023 per billion years.
C(t) = C₀ e⁻ᵏᵗ
0.375 = e⁻ᵏᵗ
e⁻ᵏᵗ = 0.375
In e⁻ᵏᵗ = In 0.375 = -0.981
-kt = -0.981
t = (0.981/0.5023) = 1.95 billion years.
Hope this Helps!!!
The percent composition of the compound.
A O-18.18%, N-21.21%, H-60.60%
<h3>Further explanation</h3>
Given
6.00 grams of oxygen,
7.00 grams of nitrogen,
20.00 grams of hydrogen.
Required
The percent composition
Solution
Total mass :
= mass of O + mass of N + mass of H
= 6 + 7 + 20
= 33 g
% O = 6/33 x 100%= 18.18%
% N = 7/33 x 100%=21.21%
% H = 20/33 x 100% = 60.6 %