Answer:The colonization of Mars has received interest from public space agencies and private corporations and has received extensive hypothetical treatment in science fiction writing, film, and art.
Explanation:
Answer:
chemical
Explanation:
The trapped carbon dioxide makes the dough rise, and the alcohol evaporates during the baking process. This is an irreversible chemical change, because by consuming the sugar, the yeast has created new substances
Ni solution could be used to remove lead from lead (II) nitrate.
Explanation:
The removal of lead from lead nitrate will take place by displacement reaction.
In displacement reaction less reactive element is displaced by more reactive element form it compound.
The reactivity is decided by the placement of metal in the activity series.
A metal which is at higher position in the activity series will be able to displace the metal or element having lower position.
From the options given we will check their position in the activity series in comparison to Pb
Cu is lower in series than Pb hence cannot displace.
Hg is placed lower in the series than Pb hence cannot displace Pb.
Ag is placed lower than Pb in the series hence cannot displace Pb.
Ni is placed above the Pb in activity series hence can displace lead.
For number 22. The answer is c. To find this look at the numbers before each compound O2 has no number which means 1, while CO2 has a 2 in front
