Answer:
what bro what like what bro huh what what huh bro
Explanation:
The situation would be that, in a sealed tube, there are 3 to 4 nails inside and a certain amount of calcium chloride was added. After three days, there will be no changes to be observed in the first tube since the oxygen is not enough to initiate a change and there is no presence of water. For the second test, the same situation is made but boiling water was filled in the tube. For this, no changes would still be observed since there is no moisture. For the last test, the same situation as the first but it is filled halfway with water. After 3 days, rust would be observed on the nails. In order for rust to happen, there should be water and oxygen. The oxygen in the early atmosphere of the Earth would react with iron present in the oceans thus producing iron ores.
Answer:
controlled experiments
Explanation:
Experiments in which all variables are identical except for one are called controlled experiments. This where an observer tests his hypothesis by looking on changes that were brought about by one variable. The results are always dependent on one adjusted variable.
