Chemistry Questions

Carbohydrates are also called as saccharides are molecular compounds made from just three elements:

carbon, hydrogen and oxygen.

Carbohydrates are:

* a source of energy for the body e.g. glucose and a store of energy, e.g. starch in plants

* building blocks for polysaccharides (giant carbohydrates), e.g. cellulose in plants and glycogen in the human body

* components of other molecules eg DNA, RNA, glycolipids, glycoproteins, ATP

Types:

1. Monosaccharides (e.g. glucose) and

2. Disaccharides (e.g. sucrose) are relatively small molecules. They are often called sugars.

3. Other carbohydrate molecules are very large called Polysaccharides such as starch and cellulose.

Shock resisting steels should have toughness.

S-5 is a silico-manganese shock resisting steel that offers good ductility.

'M' is used as a unit of molarity and stands for mole per litre i.e, number of moles of solute per liter of solution.

Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that can later be released to fuel the organisms activities.

Photosynthesis can be represented using a chemical equation.

The overall balanced equation is

              $$\begin{gathered} 6CO2 + 6H2O →Sunlight C6H12O6 + 6O2 \\ Source of Carbon & Oxygen + \\ Source of Electrons & Hydrogen + \\ Energy that drives Photosynthesis ----> \\ Sugar + Gas produced by splitting water. \end{gathered}$$

Where 

CO2 = carbon dioxide 

H2O = water

C6H12O6 = glucose 

O2 = oxygen.

The freezing point of water and melting point is 0 °C or 32 °F. The temperature may be lower if supercooling occurs.

Radioactive decay is likely to occur when the nuclei of an atom doesn't have enough binding energy to hold the nucleus together due to excess of rotons or nutrons in it.

Osmosis is the process in which water molecules move from a region of higher water potential to a region of lower potential down a water potential gradient across a partially permeable membrane. It doen't requires any additional energy to do this work. 

So, Osmosis is a Passive.

Active and passive transport processes are two ways molecules and other materials move in and out of cells and cross intracellular membranes.

1. Active transport is the movement of molecules or ions against a concentration gradient (from an area of lower to higher concentration), which does not ordinarily occur, so enzymes and energy are required.

2. Passive transport is the movement of molecules or ions from an area of higher to lower concentration. Passive transport occurs because of the entropy of the system, so additional energy isn't required for it to occur.

3. Active transport requires energy to proceed, while passive transport does not require the input of extra energy to occur.

Molecular compounds are those with covalent bonds between the elements and those elements are typically non metals.

Here in the given options, Ar is an element. NaI has an ionic bond. Hence, N2O4 has a covalent bond between the two non metals and is a molecular compound.