Answer:
I think option A is right answer
Answer: The correct option is C ( is very hard and burns cleanly).
Explanation:
COAL is a form of rock that is made up of mostly carbon amongst other elements which includes sulphur, nitrogen, hydrogen and oxygen. There are different types of coal which include:
--> anthracite ( 90% carbon)
--> bituminous coal ( 70-90% carbon)
--> lignite ( 60- 70% carbon) and
--> peat (60 % carbon).
Anthracite is the type of coal that contains the highest carbon content ( 90% carbon). This makes it very hard and is often a times referred to as HARD COAL. Anthracite is a higher quality coal for domestic and open fire heating. This is because it contains less impurities than other type of coal and thereby making it to BURN CLEANLY avoiding atmospheric pollution.
Increase in heat, molecules start to escape and it turns to vapor
Answer:
THE NEW PRESSURE OF THE HELIUM GAS AT 2.98 L VOLUME IS 124.8 kPa.
AT AN INCREASE ALTITUDE, THERE IS A LOWER PRESSURE ENVIRONMENT AND THE HELIUM GAS PRESSURE DECREASES AND HENCE AN INCREASE IN VOLUME.
Explanation:
The question above follows Boyle's law of the gas law as the temperature is kept constant.
Boyle's law states that the pressure of a fixed mass of gas is inversely proportional to the volume, provided the temperature remains constant.
Mathematically, P1 V1 = P2 V2
P1 = 150 kPa = 150 *10^3 Pa
V1 = 2.48 L
V2 = 2.98 L
P2 = ?
Rearranging the equation, we obtain;
P2 = P1 V1 / V2
P2 = 150 kPa * 2.48 / 2.98
P2 = 372 *10 ^3 / 2.98
P2 = 124.8 kPa.
The new pressure of the gas when at a height which increases the volume of the helium gas to 2.98 L is 124.8 kPa.
Answer:
I2; I–I bond length = 266 pm
Explanation:
Bond length is inversely related to bond strength. The longer the bond length, the weaker the bond. The shorter the bond length the stronger the bond. A large bond distance implies that there is poor interaction between the atoms involved in the bond. A long bond distance or bond length may even indicate the absence of covalent interaction between the atoms involved.
