Answer:
B
as the flows along the outside edge of a curve it removes rock and soil from the river bank
Answer:
When you move the burette slider to the top of a flask and add about 25 mL of NaOH to the flask, you will cause a concentration of OH- molecules. This will make the solution become a basic solution and make the litmus paper blue.
Explanation:
After reading your question, we can see that you are carrying out a test to discover the nature of the pH of a solution. This type of test uses litmus paper, which is an indicator of the presence of acids and bases, being able to determine the pH of a solution. This paper is soaked in organic ink and when placed in an acidic solution, it is red in color. However, when placed in a basic solution it has a blue color.
An acidic solution is one that has a high concentration of H+ atoms and has the ability to donate electrons. The basic solution, on the other hand, has a high concentration of OH- and has the capacity to receive electrons.
When you move the burette slider to the top of a flask and add about 25 mL of NaOH to the flask, you will cause a concentration of OH- molecules. This will make the solution become a basic solution and make the litmus paper blue, that is, the solution has the basic pH.
Answer : 0.8663 Kg of chalcopyrite must be mined to obtained 300 g of pure Cu.
Solution : Given,
Mass of Cu = 300 g
Molar mass of Cu = 63.546 g/mole
Molar mass of
= 183.511 g/mole
- First we have to calculate the moles of Cu.

The moles of Cu = 4.7209 moles
From the given chemical formula,
we conclude that the each mole of compound contain one mole of Cu.
So, The moles of Cu = Moles of
= 4.4209 moles
- Now we have to calculate the mass of
.
Mass of
= Moles of
× Molar mass of
= 4.4209 moles × 183.511 g/mole = 866.337 g
Mass of
= 866.337 g = 0.8663 Kg (1 Kg = 1000 g)
Therefore, 0.8663 Kg of chalcopyrite must be mined to obtained 300 g of pure Cu.
Answer:
Distance
Explanation:
The light-year is a measure of distance, not time. It is the total distance that a beam of light, moving in a straight line, travels in one year.
Atomic radius aka distance from the nucleus to the outermost energy level. The greater this distance, the less electrostatic attraction between these oppositely charged particles.