The dilution formula can be used to find the volume needed
c1v1 = c2v2
Where c1 is concentration and v1 is volume of the concentrated solution
And c2 is concentration and v2 is volume of the diluted solution to be prepared
c1 - 0.33 M
c2 - 0.025 M
v2 - 25 mL
Substituting these values in the equation
0.33 M x v1 = 0.025 M x 25 mL
v1 = 1.89 mL
Therefore 1.89 mL of the 0.33 M solution needs to be diluted up to 25 mL to make a 0.025 M solution
6.022x10^23 is Avogadro’s number. Use this whenever you work with Stoichiometry involving Atoms, formula units, or molecules. 1 mol of anything is always Avogadro’s number.
Multiply everything on the top= 6.93 x 10^23
Divide by everything on the bottom = 6.93 x 10^23
Answer: 6.93 x 10^23 atoms Cu.
The answer is B. A good way determine this is how far right the element is on the periodic table. The further right the element is, the more electronegative it is meaning it is more willing to accept an electron. This can be explained using the valence electrons and how many need to be added or removed to complete the octet. The further right you are, the easier it is for the element to just gain a few electrons instead of loose a bunch. Noble gases are the exception to this since they don't normally react though.
True. Nuclear fusion of hydrogen to form helium occurs naturallyin the sun and other stars. It takes place only at extremely high temperatures.
