Answer:
3Mg + Fe₂O₃ → 2 Fe + 3MgO
Explanation:
Chemical equation;
Mg + Fe₂O₃ → Fe + MgO
Balanced Chemical equation;
3Mg + Fe₂O₃ → 2Fe + 3MgO
This is the balanced equation. There are three magnesium, two iron and three oxygen atoms are on both side of equation thus it follow the law of conservation of mass.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
Answer:
Animals tend to use carbohydrates primarily for short-term energy storage, while lipids are used more for long-term energy storage. Carbohydrates are stored as glycogen in animals while lipids are stored as fats (in plants carbohydrates are stored as cellulose and lipids as oils)
Explanation:
hope this helps!
The much of the sample that would remain unchanged after 140 seconds is 2.813 g
Explanation
Half life is time taken for the quantity to reduce to half its original value.
if the half life for Scandium is 35 sec, then the number of half life in 140 seconds
=140 sec/ 35 s = 4 half life
Therefore 45 g after first half life = 45 x1/2 =22.5 g
22.5 g after second half life = 22.5 x 1/2 =11.25 g
11.25 g after third half life = 11.25 x 1/2 = 5.625 g
5.625 after fourth half life = 5.625 x 1/2 = 2.813
therefore 2.813 g of Scandium 47 remains unchanged.
Answer:

Explanation:
The molecular formula of the monohydrate formed = 
The molecular mass of the monohydrate formed = 
So, Mass = 24 + 14 + 6 × 1 + 5 × 16 = 155 g
Mass of phosphorus = 31 g
Thus,

Distance traveled by the race horse=6 furlongs
Converting the distance from furlongs to rods: 40 rods =1 furlong

Converting the distance from rods to yards, feet and miles: 5.5 yards = 1 rod, 3foot =1 yard, 1 mile = 5280 feet.

The given speed of race horse = 40.7mi/hr
Calculating the time required:

Therefore, 66.34 s is required for a race horse to run six furlongs at 40.7 miles per hour.