Answer:
1. First one is true : as per periodic table down the group , the elements has increasing order of shell & with that the London dispersion forces brings the inter-molecules close together and bromine converted into liquid .
2. second one is False because carbon-carbon bonds are not weak bonds they form mutual covalent bonds which are stronger bonds and cannot be easily disrupted .
3. A single carbon atom has the valency of 4 so it can be bonded with four hydrogen atom at the same time .
Explanation:
Answer: Tin (Sn)
Explanation: The electron configuration for tin (Sn) is shown in the picture. It's last electrons are:
5s^2 4d^10 5p^2
The valence electrons are in the 5th electron shell and include 2 each in the 5s and 5p orbitals.
Answer: It will take 29 years for a 10.0-gram sample of strontium-90 to decay to 5.00 grams
Explanation:
Radioactive decay process is a type of process in which a less stable nuclei decomposes to a stable nuclei by releasing some radiations or particles like alpha, beta particles or gamma-radiations. The radioactive decay follows first order kinetics.
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
Half life is represented by
= rate constant
Given : Strontium-90 decreases in mass by one-half every 29 years , that is half life of Strontium-90 is 29 years.
As half life is independent of initial concentration, it will take 29 years for a 10.0-gram sample of strontium-90 to decay to 5.00 grams as the amount gets half.
Answer:
53.29% of acetic acid is Oxygen
Explanation:
Step 1: Given data
Acetic acid it's molecular formula is HC2H3O2. This means it consists of 3 elements Carbon, Hydrogen and oxygen.
Step 2: the molar masses
The molecular mass of acetic acid is:
4* H = 4* 1.01 g/mole
2* C = 2*12 g/mole
2*O = 2* 16 g/mole
Total molar mass = 4+ 24+32 = 60.052 g/mole
Step 3: Calculate the mass percent
32 g of the 60.052 g is Oxygen
(32/60.052) *100% = 53.29%
53.29% of acetic acid is Oxygen.