Answer:
You just have to take the periodic table of the elements, take the element that interests you. Then, you look at the formula of the element, at the top left you find the number of neutrons and protons and at the bottom left you find the number of protons. Then you just have to make the number from the top left minus the number from the bottom left.
Explanation:
Heated, it shrinks when cooled
Answer: 4.22 grams of solute is there in 278 ml of 0.038 M 
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
where,
n = moles of solute
= volume of solution in L
Now put all the given values in the formula of molality, we get
mass of = 
Thus 4.22 grams of solute is there in 278 ml of 0.038 M
When two magnets are brought near each other, like poles repel; opposite poles attract. When a magnet is brought near a piece of iron, the iron also gets attracted to the magnet, and it acquires the same ability to attract other pieces of iron.
