Answer:
It has 4 significant figures
Explanation:
Notice the use of scientific notation to indicate that there are two zeros which should be significant. If this number were to be written without scientific notation (3,200,000,000) the significance of those two zeros would be lost and you would - wrongly - say that there were only two significant figures.
Answer:
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Explanation:
<u>1. Calculate the number of moles of NiCl₂</u>
a) Identify the known variables
- V =0.800 liters
- M = 0.531M
- n = ?
b) Formula
![M=\dfrac{n}{V}](https://tex.z-dn.net/?f=M%3D%5Cdfrac%7Bn%7D%7BV%7D)
c) Clear n
![n=M\times V](https://tex.z-dn.net/?f=n%3DM%5Ctimes%20V)
<u>g) Substitute and compute</u>
![n=0.531M/times 0.800liters=0.4248mol](https://tex.z-dn.net/?f=n%3D0.531M%2Ftimes%200.800liters%3D0.4248mol)
<u>2. Convert moles to grams</u>
a) molar mass of NiCl₂
- 129g/mol (shown in the problem)
b) Unit canceling method
Use the factors in order to cancel the units to obtain grams
![0.4248mol\times 129\dfrac{g}{mol}=54.7992g](https://tex.z-dn.net/?f=0.4248mol%5Ctimes%20129%5Cdfrac%7Bg%7D%7Bmol%7D%3D54.7992g)
Note that the mol unit appears on the numerator and denominator, so it cancels leaving just g (grams).
c) Round to 3 signficant figures
![54.8g](https://tex.z-dn.net/?f=54.8g)
Because you introduce two reactants, causing them to produce a new chemical product. :)
Answer:
Are basic:
[OH⁻] = 3.13x10⁻⁷M and [H₃O⁺] = 9.55x10⁻⁹M
Explanation:
A solution is basic when pH = - log [H₃O⁺] is higher than 7.
It is possible to convert [OH⁻] to [H₃O⁺] using:
[H₃O⁺] = 1x10⁻¹⁴ / [OH⁻]
a. [OH⁻] = 3.13x10⁻⁷M
[H₃O⁺] = 1x10⁻¹⁴ / [3.13x10⁻⁷M]
[H₃O⁺] = 3.19x10⁻⁸M
pH = - log [H₃O⁺] = 7.50
[OH⁻] = 3.13x10⁻⁷M is basic
b. pH = -log [H₃O⁺] = - log 0.000747M = 3.13.
This solution is not basic
c. [H₃O⁺] = 9.55x10⁻⁹M
pH = 8.02
This solution is also basic.
Answer:
The soil
Explanation:
The soil will cool faster because it has a lower
specific heat.
hope this helps :)