Answer:
4. Force 1 Force 2 Comparison of Forces
Friction Gravity Force 1 is equal to Force 2
Explanation:
Answer:
They all have the same number of atoms
Explanation:
Which of the following has more atoms?
One mole of zinc
One mole of gold
One mole of silver
One mole of magnesium contians
O They all have the same number of atomst
a mole of anything contains Avogadros number of 6.022X10^23 things
which has the greatest number of thing? a dozen eggs, a dozen cookies, a dozen pizzas?
a dozen is a number means 12
a mole is a number that that means 6.022 X 10^23 you calculate the molar mass from the chemical formula, but every j mole contains 6.022X10^23
particles.
just like every dozen contains 12
so
They all have the same number of atoms
C. Represents an oxidation-reduction reaction
Answer:
Explanation:
The usefulness of a buffer is its ability to resist changes in pH when small quantities of base or acid are added to it. This ability is the consequence of having both the conjugate base and the weak acid present in solution which will consume the added base or acid.
This capacity is lost if the ratio of the concentration of conjugate base to the concentration of weak acid differ by an order of magnitude. Since buffers having ratios differing by more will have their pH driven by either the weak acid or its conjugate base .
From the Henderson-Hasselbach equation we have that
pH = pKa + log [A⁻]/[HA]
thus
0.1 ≤ [A⁻]/[HA] ≤ 10
Therefore the log of this range is -1 to 1, and the pH will have a useful range of within +/- 1 the pKa of the buffer.
Now we are equipped to answer our question:
pH range = 3.9 +/- 1 = 2.9 through 4.9
