You've received great advice in the post above.

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If the water is in the gas state can go through that clothing?
My answer was no : "Because it is still the same molekul: H20 and five second later ahhh!!! Maybe yes?
Yes, the water in the gas state can go through the fabric. You are correct. Steam is an example. Humidity is an example.

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He looked at me with his very upset eyes and said Mommy whenever I asked you a question you always don't know the answer.
Some may say this is a great opportunity to explain that different people know different things. There is so much knowledge that no one person can know everything. The value of a person does not depend upon who knows the most.

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And this night He asked a phone from his father and as a reason he said that He needs to reach him any time he wants because He wants to ask question and I got more stressed but couldn;t say anything about it.
For many families a phone may not be a priority or even a possibility for a child of seven years old. Some families may wish to have the child keep a notebook or dated journal for him to write the questions he comes up with. This might allow the family to consider his questions together, enjoying a conversation on these topics and planning resources for next steps to satisfy his curiosity and further his knowledge in an area. For example, locating a library book of science experiments about the states of water (gas, liquid, solid), and conducting some experiments at home. For math, have you considered Art of Problem Solving (AoPS)?