Answer:
when CO2 gas is passed through lime water it turns milky due to the formation of calcium carbonate which formula is CaCO3.
Ca(OH)2+ CO2------ CaCO3
when excess of carbon dioxide is passed through calcium carbonate calcium hydrogen carbonate is formed and solution become colourless.
CaCO3+CO2------ Ca(HCO3)
I believe it would be the first option. It forms iron oxide (rust) when exposed to moisture and air.
Fluorine (F) will have properties similar to Bromine (Br) because it belongs to the same group as Bromine.
<h2>Heptene formed is -</h2><h2>

</h2>
Explanation:
The two possibilities when the peroxide is not present
+ HBr →
In presence peroxide,
≡
+ HBr →
- When peroxides are present in the reaction mixture, hydrogen bromide adds to the triple bond of heptane with regioselectivity.
- This reaction is opposite to that of Markovnikov's rule which says that when asymmetrical alkene reacts with a protic acid HX, then the hydrogen of an acid is attached to the carbon with more in number of hydrogen substituents, and the halide (X) group is attached to the carbon with more in number of substituents of alkyl.
- One mole of HBr adds to one mole of 1-heptane.
- The structure of heptene formed is -

Answer:
Across
2. Conduction.
3. Plates
4. Convection
5. Subduction
7. Earthquake
Down
1. Radioactive
6. Radiation
8. Sink
9. Slabpull
The clues are;
Across:
2. air molecules come in contact with warmer molecules
3. crust are made up of puzzle - like landmass called_____
4. rising and falling movement of material in the mantle
5. when tectonic plates push with each other
7. it is the result of movement of earth's plate
Down:
1. elements that play a vital role in Earth's internal heat
6. least important mode of heat transport
8. warm material rise; cool material______
9. heats build up underneath the crust