Which of the following is evidence for a chemical change? A) a substance melts B) an element easily breaks C) an element can be cut into tiny pieces D) an insoluble substance forms after combining two solutions

Consider the following reaction at equilibrium. 2co2 (g) 2co (g) + o2 (g) h° = -514 kj le châtelier's principle predicts that the equilibrium partial pressure of co (g) can be maximized by carrying out the reaction a. at high temperature and high pressure b. at high temperature and low pressure c. at low temperature and low pressure d. at low temperature and high pressure e. in the presence of solid carbon

•hydration •dissociation •dissolving which one goes to which

Select the correct lewis structure for fluorine which is group 7a element?