Answer:The visible light contains 7 colours : Violet, indigo, Blue, Green, Yellow, Orange and Red.
White colour is formed by the interference of all 7 colours, thus white light has the combination of all frequencies of visible light.
Explanation:
The correct answer is D. A solid has a high to very high melting point, great hardness , and poor electrical conduction, this is a covalent network solid. This is because of the large amount of energy required to break these bonds, the said properties are exhibited by these solids.
Answer:
The molar mass of 
is 342.145 g/mol
Explanation:
The molar mass is stated as the “mass per unit amount of substance”of a given chemical compound
is Aluminium sulphate. They easily dissolve in water. It is primarily used as a 'coagulating agent' in the drinking water purification and also in waste and sewage water treatment plants,
We know,
Atomic weight of Aluminium = 26.981
Atomic weight of Sulphur= 32.065
Atomic weight of Oxygen = 15.9994
Now molar mass of (Aluminium sulphate) is
=>2(26.981)+3(32.065+4(15.999))
=>53.962 +3(32.065+63.996)
=>53.962+3(96.061)
=>53.962+288.183
=>342.145
