What type of bond is joining the two hydrogen atoms?

Correct Answer: peptide bonds

Correct Answer: chitin

Explanation:

Many carbohydrates contain one or more modified monosaccharide units that have had one or more groups replaced or removed.

 

Chitin is one of many naturally occurring polymers. It is one of the most abundant natural materials in the world. Over time it is bio-degradable in the natural environment. Its breakdown may be catalyzed by enzymes called chitinases, secreted by microorganisms such as bacteria and fungi, and produced by some plants.

 

Chitin is composed of repeating units of N-acetylglucosamine, a nitrogen-containing form of glucose.

Correct Answer: Plant ----> Animal ----> Atmosphere

Explanation:

During daylight hours, plants capture carbon dioxide from the atmosphere and use it to make carbohydrates which is stored as starch in the plant. Animals feed on the plants and extract the carbohydrates through their digestive system. The carbohydrates, namely glucose, are used by the animals for production of ATP through cellular respiration.

 

Cellar respiration in the animals produces carbon dioxide as a waste product. The carbon dioxide is released into the atmosphere, from where it is again captured by plants and the cycle is repeated.

 

Hence, option B) Plant ----> Animal ----> Atmosphere is the path possible in carbon cycle.

Correct Answer: increase the alkalinity of the soil

Explanation:

Lime is sometimes applied to soil in order to increase the acidity of the soil.

Correct Answer: Pentagonal bipyramid

Explanation:

Hybridisation of iodine is  s p 3 d 3

 

So, the structure is pentagonal bipyramid.

Correct Answer: Oxygen and Acetylene

Explanation:

Normal Gas welding use oxygen-acetylene.

 

Depending on what materials you are welding, there are some more options that might be used.

For example - MIG/TIG use Argon, MAG use an argon-something mix.

Correct Answer: The sequence of amino acids in the polypeptide chain differs from protein to protein

Correct Answer: Vitamins B & C

Explanation:

Vitamins are essential nutrients found in foods. They perform specific and vital functions in a variety of body systems, and are crucial for maintaining optimal health.

 

The two different types of vitamins are fat-soluble vitamins and water-soluble vitamins.

 

Fat-soluble vitamins :

 Vitamins A, D, E and K ? dissolve in fat before they are absorbed in the bloodstream to carry out their functions. Excesses of these vitamins are stored in the liver, and are not needed every day in the diet.

 

Water-soluble vitamins :

Vitamins dissolve in water and are not stored by the body. Since they are eliminated in urine, we require a continuous daily supply in our diet. The water-soluble vitamins include the vitamin B-complex group and vitamin C.

 

Water-soluble vitamins are easily destroyed or washed out during food storage or preparation.

Correct Answer: Both B & C

Explanation:

Why Water Is Not an Element :

An element is a substance consisting of only one type of atom. Water consists of two types of atoms: hydrogen and oxygen.

 

water is both a molecule and a compound :

A compound forms whenever two or more atoms form chemical bonds with each other. The chemical formula for water is H2O, which means each molecule of water consists of one oxygen atom chemically bonded to two hydrogen atoms.

Thus, water is a compound.

 

It's also a molecule, which is any chemical species formed by two or more atoms chemically bonded to each other. The terms molecule and compound mean the same thing and can be used interchangeably.

 

Hence, water is both a molecule and a compound.

Correct Answer: the existence of unpaired electrons in the valence shell

Explanation:

When atoms react they do so in order to reach the lowest energy, which is the most stable. The electrons orbitals will overlap in the way that reduces the energy the most. Orbitals of similar energy will produce the greatest stabilisation.The answer you gave isn't the whole story, it depends what species is reacting with what. The effective nuclear charge on the atom will affect the energy of the valance electrons.

 

Hence, the reactivity of an atom arises from the existence of unpaired electrons in the valence shell.