What is the mass of 5.43x1045 molecules of beo

2.255 x 10²³ g

Explanation:

Data Given:

no. of molecules of BeO = 5.43 x 10⁴⁵ molecules

mass of BeO = ?

Solution:

first we will find no. of moles

Formula used

       no. of moles = no. of molecules / Avogadro's number

Where

Avogadro's number = 6.022 x 10²³

Put values in above equation

    no. of moles = 5.43 x 10⁴⁵ molecules / 6.022 x 10²³ (molecules/mol)

    no. of moles = 9.02 x 10²¹ mol

So,

There are 9.02 x 10²¹  moles of BeO of 5.43x10⁴⁵

Now we will find the mass

For this formula will be used

            No. of moles = Mass in grams/ molar mass

Rearrange the above equation

           mass in grams = no. of moles x molar mass . . . . . (1)

molar mass of BeO = 9 + 16 = 25 g/mol

Put values in equation 1

          mass in grams = 9.02 x 10²¹  moles x 25 g/mol

          mass in grams = 2.255 x 10²³ g

So,

Mass of 5.43 x 10⁴⁵ molecules of BeO = 2.255 x 10²³ g

what are the two models

explanation:

the ozone layer acts as a filter for the shorter wavelength and highly hazardous ultraviolet radiation (uvr) from the sun, protecting life on earth from its potentially harmful effects. when the sky is clear, there is an inverse relationship between stratospheric ozone and solar uvr measured at the earth's surface.