B. They work against a strong gravitational force
Explanation:
Method of prepration of sodium thiosulphate - definition
In the laboratory, this salt can be prepared by heating an aqueous solution of sodium sulphite with sulphur or by boiling aqueous NaOH and sulfur according to this equation:
Answer:
The mass of iron needed to react with the oxygen is 70 g.
Explanation:
The balanced chemical reaction between iron and oxygen is given as;
4Fe + 3O₂ ----------> 2Fe₂O₃
Molecular mass of 3O₂: 3(16 x 2) = 96 g
Molecular mass of 4Fe: 4(56) = 224 g
96 g of O₂ ---requires--------> 224 g of Fe
30 g of O₂ -------requires--------->? Fe
= (30 x 224) / 96
= 70 g
Therefore, the mass of iron needed to react with the oxygen is 70 g.
Q=m°C<span>ΔT
=(500g) x (1 cal/g.</span>°C) x (48°C-21°C) = 13500 cal
13500 cal / 1000 = 13.5 kcal
<span>"What is the caloric value (kcal/g) of the french fries?"
13.5 kcal/ 2.5 g = 5.4 kcal/g</span>
Answer:
46 percent of trees have been cut down.
Scienctists helps plants, but humans do destroy a lot of plants.
Scientists - helps increase plant growth.
Woodchoppers - helps decrease plant growth.