Answer: Option (b) is the correct answer.
Explanation:
In material bonding, there occurs Vander waal foces between the molecules in which their is either an induced or permanent dipole moment that attract molecules towards each other.
And, due to these forces the molecules are held together.
On the other hand, in a ionic bond there will always be transfer of electrons from one atom to another. This is because on atom which loses its valence electrons acquires a positive charge and another atom which gains the electrons acquires a negative charge.
Hence, these opposite charges strongly gets attracted towards each other forming a strong bond.
Whereas in a covalent bond, there will be sharing of electrons between the combining atoms.
In a metallic bond, there occurs a sea of electrons which is uniformly distributed throughout the solid substance or material.
Thus, we can conclude that the statement, Van der Waals bonds are formed by Van der Waals forces in which molecules or atoms have either an induced or permanent dipole moment to attract each other, about material bonding is correct.
Answer:
a. 300 kg of Fertilizer
b. 225 kg of fertilizer
c.400 Kg of fertilizer
d.600 Kg of fertilizer
Explanation:
The percentage composition ratio of Nitrogen, Phosphorus and Potassium bag of the given fertilizer is 40:15:10.
The percentages can be expressed as fractions as follows:
For nitrogen; 40/100 = 0.4
For phosphorus; 15/100 = 0.15
For potassium; 10/100 = 0.1
To find the quantity of fertilizer required to add to a hectare to supply the given amount of nutrients, the amount to be provided is divided by the percentage or fractional compostion of each nutrient.
Quantity of fertilizer required to add to a hectare to supply;
a. Nitrogen at 120 kg/ha = 120/0.4 = 300 Kg of fertilizer
b.. Nitrogen at 90 Kg/ha = 90/0.4 = 225 Kg of fertilizer
c. Phosphorus at 60 kg/ha = 60/0.15 = 400 Kg of fertilizer
d. Potassium at 60 kg/ha = 60/0.1 = 600 Kg of fertilizer
Answer:
242.4 g
Explanation:
RAM of KNO3=39+14+(16×3)=101
Mass=morality×RAM
101*2.4=242.4
Gunpowder is a heterogenous mixture,
Reason : the composiotion of the mixture is not uniform throughout, the mixture can be separated by a suitable method , and finally , it composes of charcoal, sulfur and potassium nitrate which is not homogeneous mixture.
The correct answers about rusting, air pollution and products of water with rock are:
Option A. oxidation
Option D. Pollutants mix with air and water to make acid rain.
Option B. clay minerals and calcium carbonate
<h3>What is rusting?</h3>
Rusting is the process by which a metal especially reacts with oxygen in the atmosphere and water vapor to form a hydrated oxide of the metal known as hydrated iron (iii) oxide. This is known as rust.
The process is an oxidation process; option A.
<h3>How does air pollution impact chemical weathering?</h3>
Air pollution is the presence of substances in air known as pollutants which makes the air impure.
Air pollution impact chemical weathering as the pollutants mix with air and water to make acid rain which weathers rocks; option D.
<h3>What products are produced when water reacts with sodium in rocks?</h3>
The reaction of water with sodium in rocks result in the formation of clay minerals and calcium carbonate also as limestone, marble or chalk; option B.
In conclusion, the presence of pollutants in air results in acid rain and hence rock weathering.
Learn more rock weathering at: brainly.com/question/2341950
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