Chemistry, 07.07.2021 22:00 tannerweberp5r8sg

Answer the two questions for 15pts

Answers: 2

Show answers

Answers

Answer from: laqu33n021

For 1: 6.68 g of nitrogen dioxide will contain $8.73\times 10^{22}$ number of molecules

For 2: The given amount of nitrogen dioxide molecules has a mass of 41.31 g.

Explanation:

According to the mole concept:

1 mole of a compound contains $6.022\times 10^{23}$ number of molecules

The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ ......(1)

For 1:

We are given:

Mass of nitrogen dioxide = 6.68 g

Molar mass of nitrogen dioxide = 46 g/mol

Putting values in equation 1, we get:

$\text{Moles of nitrogen dioxide}=\frac{6.68g}{46g/mol}=0.145mol$

Using above concept:

If 1 mole of a compound contains $6.022\times 10^{23}$ number of molecules

So, 0.145 moles of nitrogen dioxide will contain = $(0.145\times 6.022\times 10^{23})=8.73\times 10^{22}$ number of molecules

Hence, 6.68 g of nitrogen dioxide will contain $8.73\times 10^{22}$ number of molecules

For 2:

We are given:

Molecules of nitrogen dioxide = $5.41\times 10^{22}$ molecules

Using the above concept:

If $6.022\times 10^{23}$ number of molecules are present in 1 mole of a compound

So, $5.41\times 10^{22}$ number of molecules will be present in = $\frac{1mol}{6.022\times 10^{23}}\times 5.41\times 10^{22}=0.898$ moles of nitrogen dioxide

We know, molar mass of nitrogen dioxide = 46 g/mol

Using equation 1:

$0.898mol=\frac{\text{Mass of nitrogen dioxide}}{46g/mol}\\\\\text{Mass of nitrogen dioxide}=0.898mol\times 46g/mol=41.31g$

Hence, the given amount of nitrogen dioxide molecules has a mass of 41.31 g.

Answer from: Quest

- both b and d.

-since b and d are the closest coastlines then that makes it the most affected.

< 3

Max points and brainliest the diagram below shows four coastline locations on earth with respect to

Answer from: Quest

assuming that your periodic table has eighteen columns, you should highlight the four elements in the third column from the left of the table.

explanation

neutral atoms of elements after calcium contain d electrons. the energy of d orbitals of a particular main shell lies between the energy of the s and p orbitals of the next main shell. for example, electrons in the $3d$ have energy higher than those in the $4 s$ orbital while lower than those of the $4 p$ orbital.

by the aufbau principle, electrons fill orbitals one at a time, starting from those of the lowest energy. the $4s$ orbital is therefore filled right after $3p$ orbitals and before $3 d$ orbitals.

potassium has electron configuration $[\text{ar}] 4 s^{1}$ and calcium $[\text{ar}] 4 s^{2}$ . the s orbital of a main shell holds a maximum of two electrons. the next element would thus have the electron configuration $[\text{ar}] 4 s^{2} \; 3d^{1}$ and satisfy the requirements.

a neutral atom of the element contains three electrons on top of the most recent noble gas element. it should thus be placed in the third column of the periodic table. both scandium and yttrium would satisfy the conditions. an aufbau diagram indicates that the 4f orbital is filled before the 5d. however, it appears that exceptions exists for both lanthanum and actinium. neutral atoms of the two d-block elements also demonstrate the $ns^{2} \; (n-1) p^{1}$ and should be highlighted as well.