Detergents are manufactured with straight hydrocarbon chains, is to make them
soluble
biodegradable
cheaper
foamy
Correct answer is B
Biodegradable because the straight hydrocarbons are natural and slightly soluble in water. Options A,C,D do not have strength hydrocarbon chains and they could harm the environment if they are made with the detergent
When sugar is dissolve in tea, the reaction is accomplished by?
positive change
negative entropy change
no entropy change
a minimum entropy change
Correct answer is C
There is no disorderliness so no entropy change.
The elements that belong to the third period of periodic table are
Li, Be, Al and D
Na, P, O and Cl
B, C, N, and O
Na, Mg, S and Ar
Correct answer is D
Na, Mg, S and Ar is the set of elements that belong to third period of the periodic table. Option A,B,C have elements which belong to the other period in the periodic table included in them.
An oxidation state of Cr in K2Cr2O7
7
6
5
4
Correct answer is B
The oxidation state of K2Cr2O7 is +6. option A,C,D are the oxidation state of other elements like O7,C14, etc.
+2+2x+(−2×7)=0
2x=12
x=+6