How does an ionic bond form

At 450 mm hg a gas has a volume of 760 l, what is its volume at standard pressure

Write the formula for the following chemicals. 7. e. trinitrogen tetraoxide a calcium phosphate f. magnesium acetate b. potassium sulfide g nickel(iii) cyanide c carbon dioxide h. silver sulfate d. cobalt(ii) chloride

Which element would mostly likely have an electron affinity measuring closest to zero