Answer:
23.6 moles
Explanation:
From the question given above, the following data were obtained:
Mass of air = 3.6 Kg
Mass percentage of O₂ = 21%
Number of mole of O₂ =?
Next, we shall convert 3.6 Kg of air to grams (g). This can be obtained as follow:
1 kg = 1000 g
Therefore,
3.6 Kg = 3.6 Kg × 1000 / 1 kg
3.6 Kg = 3600 g
Next, we shall determine the mass of O₂ in the air. This can be obtained as follow:
Mass of air = 3600 g
Mass percentage of O₂ = 21%
Mass of O₂ =?
Mass of O₂ = 21% × 3600
Mass of O₂ = 21/100 × 3600
Mass of O₂ = 756 g
Finally, we shall determine the number of mole of O₂ in the sample of air. This can be obtained as follow:
Mass of O₂ = 756 g
Molar mass of O₂ = 2 × 16 = 32 g/mol
Number of mole of O₂ =?
Mole = mass /Molar mass
Number of mole of O₂ = 756 / 32
Number of mole of O₂ = 23.6 moles
Thus, the number of mole of O₂ in the
sample of air is 23.6 moles
Answer: infrared
Explanation: They have a longer wave length than visible light.
Answer:
This question is incomplete because of the absence of the molecules been referred to in the question. However, the molecules been referred to in the question is in the attachment below
Explanation:
First of all, we have to define lewis acid and lewis base.
A lewis acid is a substance that has the capacity to accept a pair of electrons. For example, H⁺. While a lewis base is a substance that is capable of donating a pair of electrons (to a lewis acid). For example, OH⁻.
Going by the definitions above, we can deduce the type of substance the molecules in the question (attachment) are
a. BF₃ (boron trifluoride) is a lewis acid because the central atom (as suggested to be focused on in the question) which is <u>boron, has the capacity to accept a pair of electrons</u>.
b. The central atom (carbon) in the compound (2-methyl propane) <u>also has the capacity to accept a pair of electrons</u> since it is positively charged (is electron deficient). Hence, it is a lewis acid.
c. The functional group in this compound (trimethyl borate) is the ether. Ethers are generally lewis bases because the oxygen atom in an ether can donate a pair of electrons from it's lone pair. However, the <u>presence of boron which is central to the compound</u> shows it is also a lewis acid, although weak (majorly due to the presence of the ethers).