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2 years ago

2. An atom of Be has four protons, five neutrons and four electrons. What 10 poin

Chemistry

1 answer:

Goryan [66]2 years ago

7 0

Answer:

Five ( 5 ) is the correct answer

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Structural formula for: 5 - methyl hept - 3 - enal

leonid [27]

Answer:

draw the carbon chain is containing 6 carbon then attach the aldehyde group with edge carbon in chain then put the put double bond at 3 no. carbon

6 0

2 years ago

There are molecules of carbon dioxide (CO2) in 102.5 grams.

Gekata [30.6K]

Answer:

1.403x10²⁴ molecules

Explanation:

In order to calculate how many molecules of CO₂ are there in 102.5 g of the compound, we first convert grams to moles using its molar mass:

102.5 g ÷ 44 g/mol = 2.330 mol CO₂

Now we convert moles into molecules using Avogadro's number:

2.330 mol * 6.023x10²³ molecules/mol = 1.403x10²⁴ molecules

7 0

2 years ago

1. Oxygen full electron configuration

Arada [10]

Answer:

$1s^{2} 2s^{2} 2p^{4}$

Explanation:

Oxygen has eight eletrons and six valence electrons, giving it the electron configuration of $1s^{2} 2s^{2} 2p^{4}$ .

7 0

2 years ago

How many molecules are in 7.62 L of CH4, at 87.5°C and 722 torr

pickupchik [31]

Answer: There are $1.469 \times 10^{23}$ molecules present in 7.62 L of $CH_4$ at $87.5^{o}C$ and 722 torr.

Explanation:

Given : Volume = 7.62 L

Temperature = $87.5^{o}C = (87.5 + 273) K = 360.5 K$

Pressure = 722 torr

1 torr = 0.00131579

Converting torr into atm as follows.

$722 torr = 722 torr \times \frac{0.00131579 atm}{1 torr}\\= 0.95 atm$

Therefore, using the ideal gas equation the number of moles are calculated as follows.

PV = nRT

where,

P = pressure

V = volume

n = number of moles

R = gas constant = 0.0821 L atm/mol K

T = temperature

Substitute the values into above formula as follows.

$PV = nRT\\0.95 atm \times 7.62 L = n \times 0.0821 L atm/mol K \times 360.5 K\\n = \frac{0.95 atm \times 7.62 L}{0.0821 L atm/mol K \times 360.5 K}\\= \frac{7.239}{29.59705}\\= 0.244 mol$

According to the mole concept, 1 mole of every substance contains $6.022 \times 10^{23}$ atoms. Hence, number of atoms or molecules present in 0.244 mol are calculated as follows.

$0.244 mol \times 6.022 \times 10^{23}\\= 1.469 \times 10^{23}$

Thus, we can conclude that there are $1.469 \times 10^{23}$ molecules present in 7.62 L of $CH_4$ at $87.5^{o}C$ and 722 torr.

5 0

2 years ago

(26+2)÷7 what is the answer

jek_recluse [69]

First, we have to to whatever is in the parentheses:

(26 + 2)/7
(28)/7

Now solve:

28/7
4

Hope this helps!

4 0

2 years ago

Read 2 more answers