1.26 x 10²⁴particles
Explanation:
Given parameters:
Number of moles of the compound = 2.1 moles
Unknown:
Number of particles contained in the compound = ?
Solution:
A mole can be defined as the amount of a substance that contains Avogadro's number of particles 6.02 x 10²³.
The particles mentioned here can be atoms, molecules, formula units, ions, electrons, protons, neutrons and so forth.
To solve for the number of moles:
Number of particles = number of moles x 6.02 x 10²³
Number of particles = 2.1 x 6.02 x 10²³ = 12.64 x 10²³ = 1.26 x 10²⁴particles
Learn more:
mole calculation brainly.com/question/1841136
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Based on Pauling Scale, electro negativity of Cl = 3.2, Na = 0.9 and H = 2.1
Thus, Electronegativity difference in
= 3.2 -3.2 = 0
Electronegativity difference in NaCl = 3.2-0.9 = 2.3
Similarly, Electronegativity difference in HCl = 3.2 - 2.1 = 1.1
Thus, among the listed molecules following is the decreasing order of electronegativity difference: NaCl> HCl >
Glass is a hard substance that consists of sand, soda ash and limestone. When these substances are heated together, their molecules bond to form the substance we know as glass. We use glass for many purposes, and glass bottles have become a popular method of storage, as well as being used in chemical experiments.
<span>pm stands for picometer and picometers are units which can be used to measure really tiny distances. One picometer is equal to 10^{-12} meters. We know that one centimeter is equal to 10^{-2} m so there are 10^2 cm per meter.
We can change the distance d = 115 pm to units of centimeters.
d = (115 pm) x (10^{-12}m / pm) x (10^2 cm / m)
d = 115 x 10^{-10} cm = 1.15 x 10^{-8} cm
The distance in centimeters is 1.15 x 10^{-8} cm</span>
Answer:
3.861x10⁻⁹ mol Pb⁺²
Explanation:
We can <u>define ppm as mg of Pb²⁺ per liter of water</u>.
We<u> calculate the mass of lead ion in 100 mL of water</u>:
- 100.0 mL ⇒ 100.0 / 1000 = 0.100 L
- 0.100 L * 0.0080 ppm = 8x10⁻⁴ mg Pb⁺²
Now we <u>convert mass of lead to moles</u>, using its molar mass:
- 8x10⁻⁴ mg ⇒ 8x10⁻⁴ / 1000 = 8x10⁻⁷ g
- 8x10⁻⁷ g Pb²⁺ ÷ 207.2 g/mol = 3.861x10⁻⁹ mol Pb⁺²
