Chemistry Questions

Stainless steel contains 18% chromium and 82% steel

Hydrophilic molecules readily associate with water molecules and water like molecules such as alcohols.

Mercury and Bromine both will be in liquid state at room temperature. But mercury is metal. Hence, bromine is the only non metal which is in liquid state at room temperature.

Calculation of molar mass of HNO3:

Atomic masses of H, N, O are 1, 14, 16 respectively

Now the molar mass of HNO3 is

HNO3 = 1X1 + 1X14 + 3X16

= 1 + 14 + 48

= 63 g/mol or amu.

Nitrogen (N2) forms Three Covalent Bonds to become stable.

Here the Atmomic Number of Nitrogen is 7. Because there are 2 electrons in the first orbital and 5 in the second and you still have space for 3 more. So it shares, 3 to get the stable octet. Therefore, there are 3 covalent bonds in N2.

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.

When an atom loses an electron it becomes a positive ion by acquiring negatively charged. When it loses electron, the atom's radius also decreased.