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Answer:

Explanation:
Hello,
In this case, the only source of hydrogen is in the 6 molecules of water, therefore, the atoms of hydrogen, by applying stoichiometry with the Avogadro's number is:

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Answer:
Released
Explanation:
When particles that attract each other come together, energy is usually released. The combination of the two particles is expected to result in a lower energy system. This lower energy system will be more stable than the different individual particles.
Hence, as this lower energy system is formed, the excess energy originally possessed by the particles is evolved hence energy is released when particles that attract each other are allowed to come together.
A mixture in which composition is constant throughout the mixture is said to be homogeneous mixture.
Now, oil and vinegar dressing is not considered as a homogeneous mixture because composition is not uniform.
Concrete is made up of three components. Thus, composition is not uniform, so it is not a homogeneous mixture.
A mixture of salt and pepper, when salt is mixed in pepper then the mixture is not uniform as white flecks of salt and black flecks of pepper can be seen in the mixture. Thus, it is not a homogeneous mixture.
Salt water is uniform mixture. Thus, it is a homogeneous mixture.
Thus, salt water is the correct answer.
Answer is C. in a reaction mole stays the same but mass changes and since it produced gas it means now we have less mass.