Explanation:
Fertilizers are chemically synthesized plant nutrients.
Nitrogen (N), Phosphorus (P) and Potassium (K) are macronutrients and are required in large amounts by plants. So, farmers use fertilizers in order to supply these nutrients. NPK 15:15:15 , NPK 20:20:20, NPK 15:30:15 are examples of fertilizers used to supply N, P, K to crops.
10.92N
Force = mass x acceleration
4.2kg x 1.6m/s^2 = 10.92N
Answer: (3) molecules have different molecular structures.
Explanation:
1) Oxygen (O₂) and ozone (O₃) are allotropes of each other.
2) Allotropes are different structural forms of a same element with different structures and properties, when they are in the same state: solid, liquid, gas.
3) The bonds is what define the structure and properties of the substances, so since O₂ has only two bonds and O₃ has three bonds, the properties and behaviors of the element are different.
4) Other example of allotropes are graphite and diamond: two different forms of carbon. Both, graphite and diamond are formed only by carbon atoms, but they are bonded differently so, as you know, diamond and graphite have different properties: graphite is very soft while diamond is one of the hardest known substances.
The total number of elements that one particular element can bond to can be determined by simply drawing the Lewis structure of the element.
Place the chemical symbol
Then look at the group number = valence electrons
Distribute the valence electrons around the atom.
C = 4 bonds
N = 3 bonds
O = 2 bonds