Answer:
candle.
Explanation:
Candle has more than one change chemical and physical.
Answer:
-12162.47 joules (or -12000 joules when accounting for significant figures)
Explanation (btw I used 1 cal as 4.184 joules because SI units are better):
q = m c delta T
q = (70.9) (4.184) (25 - 66)
q = (70.9) (4.184) (-41)
q = -12162.47 joules
The number of atoms in one mole of any substance is measured by Avogadro's number. The value of Avogadro's number is 6.023 x 10 ^23. It is named after scientist Avogadro who proposed this number. 12 grams of carbon-12 represents 1 mole of carbon-12. For this reason, the number of atoms present in 1 mole of any substance is 6.023 x 10 ^23. Therefore, the number of atoms present in 1 mole carbon-12 is 6.023 x 10^23.
(Answer) This unit is the number of atoms in 12 grams of carbon-12 and known as Avogadro's number.
Answer:
Point of incidence: The point on the surface where the incident ray strikes the surface is called the point of incidence. Reflected ray: The ray of light that bounces back from the surface of an object is called a reflected ray of light.
Explanation:
Search
Answer: The fourth material that is added to the blast furnace is HOT AIR which provides OXYGEN for used for combustion of carbon (Coke).
Explanation:
Iron is the second most abundant metal found in the earth's crust after aluminium. It is not found in the free metallic state but are extracted from rocks which are rich in iron that contains other materials. These are known are iron ores and the most common iron ores are haematite ( Fe2O3).
Iron can be extracted from its ore with the used of blast furnace. The materials used for extraction of iron includes:
--> Coke
--> haematite( iron ore)
--> limestone and
--> Hot air.
The iron ore is first roasted in air so that iron(III)oxide is produced. The iron(III)oxide is then mixed with coke and limestone and heated to a very high temperature. Hot air is introduced into it from the bottom of the furnace. The coke is oxidizes the the oxygen in the hot air blast to liberate carbondioxide.
