Three scientists are credited with the development of cell theory. Matthias Schleiden observed that all plants were made of cells; Theodor Schwann observed that all animals were also made of cells; and Rudolf Virchow observed that cells only come from other cells.
When the charged balloon is brought near the wall, it repels some of the negatively charged electrons in that part of the wall. Therefore, that part of the wall is left repelled.
<u>Explanation</u>:
- Balloons don't stick to walls. However, if you rub the balloon on an appropriate piece of material such as clothing or a wall, electrons are pulled from the other material to the balloon.
- The balloon now as more electrons than normal and therefore has an overall negative charge. Two balloons like this will repel each other.
- The other material now has an overall positive charge. Because opposite charges attract, the balloon will now appear to stick to the other material. If you didn't rub the balloon first, it's charge would be neutral and it wouldn't stick to the wall.
The balanced chemical formula should be Al2(SO4)3 + 6NaOH = 2Al(OH)3 + 3Na2SO4
Therefore the coefficient of Al(OH)3 is 2!
Hope that helps :)
The first solution or a I think is the correct answer
Answer:
The periodic table
Explanation:
The periodic table can show the atomic number and atomic mass of any atoms easily. To convert grams of water to moles of water, you need to know the atoms that made up water molecules then find out their molecular mass. Water is made of two hydrogens and one oxygen atoms. Then you can find the atomic mass of hydrogens is 1 while oxygen is 16. The molecular mass of water will be 2*1 + 16= 18g/mol.