Answer:
20.5 × 10²³ molecules of He
Explanation:
Given data:
Number of moles of He = 3.40 mol
Number of molecules of He = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
For 3.40 moles of He:
3.40 mol × 6.022 × 10²³ molecules
20.5 × 10²³ molecules of He
Answer: 1.2 Moles of Nickel
Explanation:
So you have to transfer grams to moles.
You do this by dividing your beginning mass by the atomic mass of the element (found on the periodic table).
1 mole is equal to the atomic mass of the element. The atomic mass of Nickel is 58.6934 rounded to the proper significant figures will be 59.
72 Grams Nickel / 59 grams = 1.2 moles of Nickel
Answer:
![r = k . [CO] .[Cl_{2}]](https://tex.z-dn.net/?f=r%20%3D%20k%20.%20%5BCO%5D%20.%5BCl_%7B2%7D%5D)
Explanation:
Let´s consider the following reaction:
CO + Cl₂ ⇒ COCl₂
The general rate law is:
![r = k . [CO]^{m}. [Cl_{2}]^{n}](https://tex.z-dn.net/?f=r%20%3D%20k%20.%20%5BCO%5D%5E%7Bm%7D.%20%5BCl_%7B2%7D%5D%5E%7Bn%7D)
where,
r is the rate of the reaction
k is the rate constant
[CO] and [Cl₂] are the molar concentrations of each reactant
m and n are the reaction orders for each reactant
Since the reaction is first order in CO, m = 1. The overall order is the sum of all the individual orders. In this case, the overall order m + n = 2. Then,
m + n = 2
n = 2 - m = 2 - 1 = 1
The reaction is first order in Cl₂.
The rate law is:
![r = k . [CO]. [Cl_{2}]](https://tex.z-dn.net/?f=r%20%3D%20k%20.%20%5BCO%5D.%20%5BCl_%7B2%7D%5D)
1) endothermic
2)exotgermic
3)exotgermic
<span>quartz (SiO2) is a compound. A compud is the combination of two or more elements. It is a compound because three elements are formed, the silicon and the two atoms of oxygen.</span>
