E the given conversion factors below to convert between mass and number of representative par plecules, and ions)
oblem: How many molecules of methane (CHA) if there are 9.65 gram of methane ?

3.63 x 10²³molecules

Explanation:

Given parameters:

Mass of methane = 9.65g

Unknown:

Number of molecules  = ?

Solution:

To solve this problem first, we find the number of moles of the given compound or molecule first.

The given molecule is methane;

    CH₄;

     Number of moles  =

Molar mass of CH₄   = 12 + 4(1)  = 16g/mol

    Number of moles  =   = 0.603moles

So;

From mole concept;

      1 mole of a substance contains 6.02 x 10²³ molecules

    0.603moles of methane will contain 0.603  x  6.02 x 10²³

                                                               = 3.63 x 10²³molecules

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.