Answer:
1 million years
Explanation:
The half life of a radioactive isotope refers to the time it takes for the radioactive isotope to decay to half of its original amount.
The half life of a radioactive isotope is independent of the amount of starting material. Hence, whether the amount of starting material is small or large, the half life of the substance remains the same.
Hence the half life of 2 green marbles and 500,000 green marbles is 1 million years.
Answer:
1.2 atm
Explanation:
Given data
- Volume of the gas in the tank (V₁): 200.0 L
- Pressure of ethylene gas in the tank (P₁): ?
- Volume of the gas in the torch (V₂): 300 L
- Pressure of the gas in the torch (P₂): 0.8 atm
If we consider ethylene gas to be an ideal gas, we can find the pressure of ethylene gas in the tank using Boyle's law.

Answer:
22)convex
23)sun (sunlight reflect of the off the surface of the moon
24)because of the way the atmosphere interacts with sunlight
25) transparent : glass,contact lenses,water,air
translucent: wax paper, oil paper, thin sheets
opaque : plastic, wood, leather
26)when light react with opaque: none of it passes though
when it reacts with transparent : it passes through
when it react with translucent : only some of it passes through, the light does not pass directly through the material
Explanation:
24 blue light is scattered in all directions by the tiny molecules of air in earth's atmosphere
This compound is Boron selenate. Molar mass of B2(SeO4)3 is 450.4948 g/mol.
Answer:
Correc option: 
Explanation:
size of atom : it says somthing about how many shell present in a particular atom or ion and it can also be evaluated on the basis of radius of atom.
Br^- and Kr has highest number of shell as compared to other group of species .
Na ,S , Mg ,P all are from 3rd period but Kr and Br^- in the 4th period so size of species of this group will more,
Size increases on increasring the shell number