Predict which of the following transition metal ions has a color: cr3+ cd2+ hg+2 v2+. explain

Jewelweed, a flowering plant, has seed pods that burst open when touched and forcefully eject their seeds. these structures are favorable because they a. can cause genetic changes to occur. b. prevent germination within the seed pod. c. aid in the dispersal of the species. d. attract insects that aid in pollination.

Marcel just purchased 1.69 grams of iron fillings in order to make living putty for his 6 year old niece. how many moles of iron are made in his sample?

If 16.00g of hydrogen gas reacts with 126.73g of oxygen, how many grams of water are yielded? (both reactants are completely consumed in the reaction.)