Answer:
A
Explanation:
The group number of an element is equal to the number of electrons the outermost shell (or highest energy level) contains
Answer: The ratio of atoms in calcium bicarbonate ; Ca : H : C : O = 1:2:2:6.
The ratio of atoms in lithium sulfide; Li : S = 2 : 1
Explanation:
In calcium bicarbonate:
In a molecular formula of calcium carbonate there are:
Number of Calcium atoms = 1
Number of Hydrogen atom = 1 × 2 = 2
Number of Carbon atoms = 1 × 2 = 2
Number of Oxygen atoms = 3 × 2 = 6
So, Ca : H : C : O = 1 : 2 : 2 : 6
In lithium sulfide :
In a molecular formula of lithium sulfide there are:
Number of Lithium atoms = 1 × 2 = 2
Number of Sulfur atoms = 1
So, the Li : S = 2 : 1
Answer: The correct answer is option (D)
Explanation:
These aurora are also known as polar lights or northern lights( north poles) or southern lights(south pole) . This is caused by the interaction between the charged particles from the sun with particles present in the upper atmosphere of the earth's atmosphere. The layer in which these interaction takes place is Thermosphere (with high temperature).
Hence, the correct answer is option (D).
A. Two electrodes separated by an electrolyte that can generate an electrical current.
Answer:
Explanation:
The crabs cannot see the plankton they eat near the ocean floor. For the crabs to see the plankton, some color of visible light would need to reach the plankton so that it can be reflected into the crabs' eyes.
