Answer:
Chemical reaction, compound, molecule, covalent bonds, ionic bonds, ions. (first page)
Oxygen and hydrogen, 1 hydrogen 2 oxygen, H2O, a covalent bond, then mark off is always a liquid. (Second page)
Explanation:
Answer:
The element belongs to group 15 of the present periodic table
Explanation:
Isotopes have the same proton number, what differs is that they have different number of neutrons.
Now since the half-sum of their neutrons is 19, the total number of neutrons would be 19 * 2 = 38 neutrons.
Also, their masses add up to be 68, since the total mass equals sum of neutrons and sum of protons, this means that the total number of protons is 68-38 = 30
Since this is equal in both isotopes, this means that the proton number of the element is 30/2 = 15
The atomic number is the number of protons in the nucleus of an atom. Since the atomic number is 15, this element is phosphorus and it belongs to group 15 of the present periodic table
Answer:
Explanation:
Given that the volume is 
The air flows (F) at the rate of 
. The concentration of carbon monoxide in the air is 5%.
Let Q be the amount of the carbon monoxide present in the room at time t. then,
Also,
Thus,
It keeps the plant upright, and it provides nutrients
Answer:
- Gravitational force
- Normal force
Explanation:
These act as the action-reaction forces.
