Which one of the following has different number of moleculcs ? (All are kept at normal temperature and pressure)

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Q: 15 (NDA-II/2016)

Which one of the following has different number of moleculcs ? (All are kept at normal temperature and pressure)

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,2,7,3,4,0,2

keywords: 

{'moleculcs': [0, 0, 0, 1], 'hydrogcn': [0, 0, 0, 1], 'nitrogen': [1, 1, 0, 2], 'carbon': [1, 0, 4, 5], 'different number': [0, 0, 1, 2], 'oxygen': [3, 0, 1, 0], 'gram': [3, 0, 3, 2], 'normal temperature': [0, 1, 0, 0], 'pressure': [0, 0, 0, 1]}

In this question, we need to determine which compound has a different number of molecules compared to the others at normal temperature and pressure.

To do this, we can use the concept of moles. A mole is a unit that represents a specific number of particles, which is approximately 6.022 x 10^23 particles.

The formula to calculate the number of moles is:

Number of moles = Mass of substance / Molar mass

Let`s calculate the number of moles for each option:

Option 1: Hydrogen (H2)

Molar mass of hydrogen = 1 gram/mol

Number of moles = 3 grams / 1 gram/mol = 3 moles

Option 2: Oxygen (O2)

Molar mass of oxygen = 16 grams/mol

Number of moles = 48 grams / 16 grams/mol = 3 moles

Option 3: Nitrogen (N2)

Molar mass of nitrogen = 28 grams/mol

Number of moles = 42 grams / 28 grams/mol = 1.5 moles

Option 4: Carbon (C)

Molar mass of carbon = 12 grams/mol

Number of moles = 2 grams / 12