The more numbers after the decimal point there are, the more precise the instrument which recorded it is. For example, if one instrument during seismic activity records that the magnitude of the earthquake was 2.3, and another instrument recorded that it was 2.3645, the second instrument would have shown to be more precise.
Answer:
4.34.
Explanation:
<em>∵ pH = pKa + log [salt]/[Acid]</em>
∴ pH = - log(Ka) + log [salt]/[Acid]
∴ pH = - log(6.8 x 10⁻⁵) + log(0.75)/(0.50)
<em>∴ pH = 4.167 + 0.176 = 4.343 ≅ 4.34.</em>
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Answer:
Normality N = 0.2 N
Explanation:
Normality is the number of gram of equivalent of solute divided of volume of solution, where the number of gram of equivalent of solute is weight of the solute divided by the equivalent weight.
Normality is represented by N.
Mathematically, we have :

Given that:
number of gram of equivalent of solute = 90 milliequivalents 90 × 10⁻³ equivalent
volume of solution (HCl) = 450 mL 450 × 10⁻³ L

Normality N = 0.2 N
Answer:
C) 1.15 × 10⁻⁷ mm
Explanation:
Step 1: Given data
Average distance between nitrogen and oxygen atoms: 115 pm
Step 2: Convert the distance to meters (SI base unit)
We will use the conversion factor 1 m = 10¹² pm.
115 pm × (1 m/10¹² pm) = 1.15 × 10⁻¹⁰ m
Step 3: Convert the distance to millimeters
We will use the conversion factor 1 m = 10³ mm.
1.15 × 10⁻¹⁰ m × (10³ mm/1 m) = 1.15 × 10⁻⁷ mm
Answer:
3
Explanation:
A cyclic event is one that happens repeatedly.
The appearance of Hailey's Comet is a cyclic event because it has happened in various occasions in the past on a regular schedule as predicted. We have every reason to believe that the appearance of Hailey's Comet every 75 years will continue to be happen until the comet ceases to exist.