Answer:

We do not have
- the amount of substance.

The molecular weight (
) of Bromine is 80.


Answer:
Excretory system, and Kidney.
Explanation:
The excretory system helps to regulate the chemical composition of the body fluids by removing metabolic waste such as undigested food, intestinal bacteria, and old cells and helping to retain the proper amount of water, nutrients, and salts in the body.
The main function of the kidney is to filter the blood, kidney help to remove waste from the body as urine, control fluid balance in the body, and keep the right level of electrolytes. Each kidney is bean-shaped in structure and 4-5 inches long in size.
Answer:
Structure has been shown below
Explanation:
- In a Lewis structure, least electronegative atom is taken as central atom (except H)
- Total valence electrons of constituting atoms are used to construct Lewis structure
- A bond between two atoms are represented by a horizontal line or a dotted line (two dots).
- Spatial rearrangement of atoms are neglected in Lewis structure.
- H has one valence electron and O has six valence electrons. So, total valence electrons in
are 8 - Lewis structure of
has been given below.
Answer:
Explanation:
molar volume=moles*given volume
for molar concentration we use two formulas molarity and molality
molarity=no of moles/volume
molality=no of moles/kilogram
Answer: 8.1 days
Explanation:
Expression for rate law for first order kinetics is given by:

where,
k = rate constant
t = age of sample
a = let initial amount of the reactant = x
a - x = amount left after decay process=
a) to find rate constant
Half life is the amount of time taken by a radioactive material to decay to half of its original value.


b) for completion of one fourth of reaction



Thus after 8.1 days , one fourth of original amount will remain.