Answer:
The answer is in the explanation.
Explanation:
A buffer is defined as the aqueous mixture of a weak acid and its conjugate base or vice versa. Buffers are able to avoid the pH change of a solution when strong acid or bases are added (As NaOH).
Based on the experiment, it is possible that the solution Z was a buffer and Y another kind of solution. For this reson, pH of the solution Y changes much more than the pH of solution Z changes despite the amount of NaOH added is the same in both solutions.
Answer:
A. Second
Explanation:
The S.I unit of time is in Seconds.
The S. I unit is known as the metric system is the most commonly used system of reporting scientific measurements in the world today. Other units are the imperial units.
It is the international system of unit used in almost all countries. The seven basic SI units are:
Quantities Units
- Length meters(m)
- Time seconds(s)
- Amount of substance moles(mol)
- Mass kilograms(kg)
- Luminous intensity candela(cd)
- Temperature kelvin(K)
- Electric current ampere(A)
The SI unit of time which measures the duration of an activity or event is therefore given as seconds(s)
Answer:
1.4e+8 bismuth atoms
Explanation:
If 10³ mm = 10¹² pm
then 44 mm = X pm
X = (44 × 10¹²) / 10³ = 44 × 10⁹ pm (which is the cookie diameter in picometers)
Now we can calculate the number of bismuth atoms needed to span the diameter of the cookie:
number of bismuth atoms = cookie diameter / bismuth atom diameter
number of bismuth atoms = 44 × 10⁹ / 320 = 0.1375 × 10⁹ atoms = 1.375 × 10⁸ atoms
And now to respect the answer format requested by the problem:
1.375 × 10⁸ = 1.375e+8 ≈ 1.4e+8
