Nancy uses one 9-volt battery in each circuit. She uses the same amount and type of wire in each circuit. She also uses the same type of light bulbs in each circuit.
Which of the following is a control in Nancy's experiment?

Consider the following reaction at equilibrium: c(s)+h2o(g)⇌co(g)+h2(g) predict whether the reaction will shift left, shift right, or remain unchanged upon each of the following disturbances. a) c is added to the reaction mixture. b) h2ois condensed and removed from the reaction mixture c) co is added to the reaction mixture d) h2 is removed from the reaction mixture.