A substance that undergoes change during a reaction, usually from coming in contact with another substance
Answer: helium(He)
Explanation: Helium has only 2 electrons in the outermost energy level, but all of the other elements in its column have eight.
Answer:
Option A
They are located near the equator
Explanation:
From the diagram, we can observe that all the rain forest zones occur near the equator.
This is because on an annual basis, the equator receives the highest concentration of solar radiation in the whole Earth. This implies that the rate of evaporation of water from the water bodies present is high, and consequently, the amount of rainfall is high also. This abundant sunshine and high rainfall leads to the growth of the tropical rain forests at those regions
Types of Bonds can be predicted by calculating the
difference in electronegativity.
If, Electronegativity difference is,
Less
than 0.4 then it is Non Polar Pure Covalent
Between 0.4 and 1.7 then it is Polar Covalent
Greater than 1.7 then it is Ionic
For Br and Br,
E.N of Bromine = 2.96
E.N of Bromine = 2.96
________
E.N Difference
0.00 (Non Polar/Pure Covalent)
For N and O,
E.N of Oxygen = 3.44
E.N of Nitrogen = 3.04
________
E.N Difference
0.40 (Non Polar/Pure Covalent)
For P and H,
E.N of Hydrogen = 2.20
E.N of Phosphorous = 2.19
________
E.N Difference 0.01 (Non Polar/Pure Covalent)
For K and O,
E.N of Oxygen = 3.44
E.N of Potassium = 0.82
________
E.N Difference 2.62 (Ionic)
The answer would be D. This is because sulfur is on it's own, meaning one. while tri is a prefix for three so there are three oxygen atoms.