Asample of a solid labeled as nacl may be impure. a student analyzes the sample and determines that it contains 75 percent chlorine by mass. pure nacl contains 61 percent chlorine by mass. which of the following statements is consistent with the data?
a- the sample contains only nacl
b- the sample contains nacl and nai
c- the sample contains nacl and kcl
d- the sample contains nacl and licl

The impure sample contains a mixture of NaCl and LiCl.

WHAT IS A PURE SUBSTANCE?

A pure substance is that substance that contains a fixed or constant chemical composition.

According to this question, a pure composition of NaCl contains 61 percent chlorine by mass. However, the solid sample in this question contains 75 percent chlorine by mass. This means that an impurity that increased the chlorine content (KCl or LiCl) is present in the sample.

Therefore, impure sample contains a mixture of NaCl and LiCl.

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c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.