39. What item is used to hold the matrix band in contact with the interproximal area of the preparation?
A. Matrix
C. Wedge
B. Cotton roll
D. Retainer

Cucl2 + 2nano3 cu(no3)2 + 2nacl what is the percent yield of nacl if 31.0 g of cucl2 reacts with excess nano3 to produce 21.2 g of nacl? 49.7% 58.4% 63.6% 78.7%

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

Why does a plastic bottle that is sealed at a high altitude change it’s shape when taken to lower altitude