Achemist measures the energy change ? h during the following reaction:

2fe2o3(s) ? 4feo(s) + o2(g) =? h560.kj
this reaction is.

(a) endothermic
(b) exothermic

suppose 66.6 g of fe2o3 react. will any heat be released or absorbed? |

(a) yes, absorbed
(b) yes released.
(c) no

Why is the bond angle in a water molecule less than the bond angle of methane? a. the central oxygen atom in water has two lone pairs of electrons, whereas the central carbon atom in methane has no lone pairs. b. the central hydrogen atom in water has one lone pair of electrons, whereas the central carbon atom in methane has two lone pairs. c. the central oxygen atom in water has four lone pairs of electrons, whereas the central carbon atom in methane has only one lone pair. d. the central oxygen atom exerts more repulsive force on surrounding atoms than the central carbon atom in methane does. reset next

Adeuteron, 21h, is the nucleus of a hydrogen isotope and consists of one proton and one neutron. the plasma of deuterons in a nuclear fusion reactor must be heated to about 3.02×108 k . what is the rms speed of the deuterons? express your answer using two significant figures.

In one or two grammatically correct sentences, write a definition for the term molecule geometry