Traditionally they include boron from group 3A, silicon and germanium in group 4A, aresnic and antimony in group 5A and tellurium from group 6A, although sometimes selenium, astatine, polonium and even bismuth have also been considered as metalloids. Typically metalloids are brittle and show a semi-metallic luster.
The six commonly recognised metalloids are boron, silicon, germanium, arsenic, antimony, and tellurium. Five elements are less frequently so classified: carbon, aluminium, selenium, polonium, and astatine.
This is a D. combustion reaction
That is because you add O2 which is necessary for a combustion, while the results are CO2 and water. What you are missing is a ---> after the 2O2 (g)
Answer:
Explanation:
solar cell - converts sunlight into electricity
geothermal energy - heat produced within the Earth
wave energy - turns turbines along coastlines
hydroelectricity - water falling through dams turns turbines, generates electricity
Option A: Clouds
In the morning, air is cool and as sun begins to rise it starts increasing the temperature of air. By time, the air becomes warmer and warmer. Depending upon the surrounding conditions, air in different areas heat up at different rates.
Due to this heating, thermal formation takes place, this is due to uneven heating of surface of earth. The thermal formation at surface causes difference in temperature of surface of the earth and air around it. The warm air has tendency to rise thus, the air in the thermal rise and expand. Due to expansion it cools down, this process continues till the temperature of thermal air reaches equals to the temperature of surrounding air. This results in the formation of cloud.
Thus, when a humid air mass rises into a cooler temperature area, clouds formation takes place