Answer:
Quartz is not pure in this rock.
Explanation:
When quartz shows effervescence in contact with an acid, it means that it is not in its pure state, but rather related to other substances that may be cementing the quartz. This effectiveness is caused by substances that do not react like quartz, such as calcite.
In this case, we can conclude that in relation to the calcium-rich rock shown in the question above, the calcium is not pure, but it is likely to be related to calcite, or other material that does not react to acid.
Answer:
Chemical weathering is different from mechanical weathering because the rock changes, not just in size of pieces, but in composition. ... Chemical weathering works through chemical reactions that cause changes in the minerals.
Geographycally speaking, Russia is situated North and West of China.
They are both countries which expand on a vast territory and confine with many countries:
China also confines with: North Korea on the East, Mongolia on the North, Kazakistan, Kirghizistan, Tagikistan, Afghanistan, Pakistan and India in the West, and Nepal, Bhutan, Myanmar, Laos and Vietnam in the South.
While Russia confines with: Kazakistan, Mongolia and Georgia on the South, Ucraina, Belarus, Latvia, Estonia and Finland on the West.
