The fourth period contains 18 elements, beginning with potassium and ending with krypton. As a rule, period 4 elements fill their 4s shells first, then their 3d and 4p shells, in that order; however, there are exceptions, such as chromium.
Cr. I think
Answer:
C
Explanation:
If you add enough heat to a solid it eventually becomes a liquid
Answer:
No. 4
Explanation:
Bacteria are produced from pre existing bacteria
A. 2.9384 x -7
B. 9.0832 x 9
C. 3.4455 x -3
D. 2 x 3
Answer:
The correct answer is option D. "Russia and Canada".
Explanation:
Russia and Canada are countries with extensive areas of arctic tundra conditions. These two countries could use these areas as a source of gas or methane hydrates since it have been demonstrated that tundra is rich in these gasses, which are trapped inside the ice. Unfortunately methane is a powerful greenhouse gas, and its release to the atmosphere is an environmental concern that rises from the climate change phenomena.