Explanation:
A chemical bond which is formed in between positively charged atoms when there is sharing of free electrons in a lattice of cations is known as a metallic bond.
In a pure metal, atoms are surrounded by free moving valence electrons which move from one part of metal to another.
Thus, we can conclude that pure metals are held together by metallic bonds due to attraction between mobile valence electrons and positively charged metal ions.
Answer: Option (a) is the correct answer.
Explanation:
A protein part of an enzyme is known as an apoenzyme. An apoenzyme combines with a cofactor, it is known as holoenzyme.
Without a cofactor an apoenzyme cannot function as cofactor helps in the formation of an active enzyme system and provides a specific site on enzyme for the substrate.
Whereas a non-protein chemical compound or metal ion that helps in the activity of enzyme as a catalyst is known as a cofactor. A metal ion cofactor can be bound directly to the enzyme or to a coenzyme.
The organic non-protein molecules which bind to the protein molecule to form an active enzyme is known as a coenzyme. Coenzymes are small size molecules which help the enzymes to act as a catalyst.
Therefore, we can conclude that the statement an apoenzyme can catalyze its reaction without its cofactor, is false.
Presumptive tests, also known as preliminary tests or field tests, allow drugs to be quickly classified into a particular chemical group, but do not unequivocally identify the presence of a specific chemical compound.
Answer:
The glass of water weigh once the antacid pill has dissolved will be less than the 179 grams due to evolution of carbon dioxide.
Explanation:
Mass of effervescent antacid pill = 4.00 g
Mass of water = 85 g
Mass of glass = 90 g
Total mass of the substances together : 4.00 g + 85 g + 90 g = 179 g
Effervescent antacid pill , moment it get dissolved in water carbon dioxide gas is evolves and escape from the solutions.
This means that mass of the weight of the glass of water with antacid dissolved in it will be less than 179 grams.
