Answer:
Nucleic acid is an important class of macromolecules found in all cells and viruses. Deoxyribonucleic acid (DNA) encodes the information the cell needs to make proteins.
A related type of nucleic acid, called ribonucleic acid (RNA), comes in different molecular forms that participate in protein synthesis.
<u>The troposphere: </u>
H. This layer can have thunderstorms or clear, sunny skies.
A. The biosphere interacts most with this layer.
<u>The stratosphere:</u>
B. It is the second layer from Earth's surface.
G. Winds are strong and steady in this layer.
<u>The mesosphere:</u>
E. It is heated by the ozone layer beneath it.
D. This layer is where most meteor showers occur.
<u>The thermosphere :</u>
F. It contains the ionosphere and exosphere.
C. It contains layers of single, unmixed gas.
<u>Explanation:</u>
Depending on the Earth's temperature the atmosphere can be separated into layers. The troposphere, the stratosphere, the mesosphere and the thermosphere are those layers. The lowest layer is named as Troposphere (0-10 km from the Earth outer surface), it comprises about 75% of the atmosphere's total air and nearly most the water vapor.
Stratosphere (10-30) includes much of the surface ozone. The change in height temperature arises as this ozone absorbs ultraviolet (UV) radiation from the sun. The temperature in Mesosphere (30-50 Km) declines again with height, hitting a minimum of about -90 ° C at the "mesopause." Above this thermosphere (50-400 Km) is settled which is a area where temperatures rise with height once again. The penetration of intense UV and X-ray radiation from the sun induces this temperature rise.
Answer:
Metal
Explanation:
Lithium (Li), chemical element of Group 1 (Ia) in the periodic table, the alkali metal group, lightest of the solid elements. The metal itself—which is soft, white, and lustrous—and several of its alloys and compounds are produced on an industrial scale.
Atomic number: 3
Atomic weight: 6.941
The answer is 2 electrons.
The electron configuration of calcium is 2:8:8:2
Calcium has two electrons in its outermost shell. These are its valence electrons and are the ones used in bonding with other elements. Valence electrons of an atom are those electrons that are in its outer energy shell or that are available for bonding.
Calcium is a metal. When metals react with non-metals, electrons are transferred from the metal atoms to the non-metal atoms forming ions. The resulting compound is known as an ionic compound.
For example, when calcium metal reacts with chlorine gas, calcium gives up its two valence electrons and Chlorine accepts them resulting in a new substance called calcium chloride in which the two elements have ended up forming ionic bonds.
Answer:

Explanation:
<u>According to Arrhenius concept of acid and base:</u>
"When a base in a solution, produces/yields OH- (Hydroxide) ions."
So, when a base is dissolved in a solution, it produces OH- ions.
<u>For example:</u>
NaOH ⇄ Na⁺ + OH⁻ (So, it is a base)
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Hope this helped!
<h3>~AH1807</h3>