Answer:
0.007 M
Explanation:
pH is defined as the negative logarithm of the concentration of hydrogen ions.
Thus,
pH = - log [H⁺]
The expression of the pH of the calculation of weak acid is:-
Where, C is the concentration = ?
Given, pH = 3.45
So, for ,
C = 0.007 M
Answer:
Spices
Explanation:
Herbs are the leaves.
Vegetables are the seeds.
Fruits are the seeds.
So spices are the only option left.
For the first one, you have to find one that has both a metal and a nonmetal in it, plus potassium. Bonds between nonmetals are called covalent because they share electrons and a bond between a metal and a nonmetal is an ionic bond because they exchange electrons.
Potassium chloride is KCl. Only an ionic bond.
Potassium hydride is KH. Only an ionic bond.
Potassium nitrate is KNO3. There we go, that has a covalent bond between the nitrogen and oxygen, and an ionic bond between potassium and the nitrogen and oxygen.
For the second one, potassium chloride is the answer because the other three also have covalent bonds. Chloride is the only one that isn't a compound.
I divided the volume by a 1000 because it must be in litres, but it wont make any difference because they will cancel out, but you must always convert it to L or dm3 unless it says in the question something else.
Answer:
Explanation:
When adding or subtracting values, you must round your answer to the same "place" as the measurement with its last significant figure furthest to the left.
That is, you round off to the same number of decimal places as the measurement with the fewest decimal places.
The measurement of 28.1 cm has one digit after the decimal point, so you round the sum to have only one digit to the right of the decimal.
However, the number to be dropped (51) is greater than 5 with only zeros or nothing following the 5.
You must round up the answer. You increase the last significant digit by one.