Answer:
Physical Properties of Carbon:
Carbon is a unique element. It occurs in many forms. Some examples of the pure form of carbon are coal and soot.
It is soft and dull grey or black in colour.
One of the most important compounds of carbon is the charcoal, which is formed when carbon is heated in the absence in of air.
It occurs in a number of allotropic forms. Allotropes are nothing but forms of an element with varying physical as well as chemical properties.
The density of the different forms of carbon depends upon the origin of these elements. You will find some forms of carbon which are pure and some forms which are not pure like coal which is the mixture of both carbon and hydrogen.
Chemical Properties of Carbon
Carbon compounds generally show 4 reactions, they are
Combustion reaction
Oxidation reaction,
Addition reactions
Substitution reaction.
As we all know that carbon in all forms needs oxygen, heat, and light and forms carbon dioxide. When it is burned in air to give carbon dioxide, it is called as combustion.
Let us get the concept of this using some examples when it is burnt in the air: When methane CH4 is burnt in the presence of oxygen it gives us carbon dioxide, heat, and light.
Explanation:
The independent variable is how much weight you add to the boat.
The dependent variable is: Did it or did it not sink yet ?
<h2>Answer:</h2>
All the energy sources are correctly matched with their category.
Explanation:
Renewable energy sources:
These are energy sources which can be replenished as they don't in involves the irreversible phase change.
These resources can never be ended as they can be used again and again.
Wind, geothermal, biomass, bio gas are example of renewable energy sources.
Non renewable energy sources:
These are the energy source which can never be replenished after one time use. They undergo the chemical irreversible change.
These sources are lacking with the passage of time because they can never be reused.
Oil, gas, coal and natural gas are examples.
Answer:
C
Explanation:
Radiation affects both cancer cells and healthy cells, but it affects cancer cells more.
Answer: (1) The resistance increases and the current decreases.
Explanation:
When the temperature of the filament increases, the vibrational energy of the constituent atoms increases which leads to increase in inter-atomic collision. Thus, the resistance would increase. The increases in resistance would obstruct the flow of charges more leading to decrease in the value of the current.
Hence, when the temperature of the filament increase, the resistance increases and current decreases.
