Please help! Samira watched a demonstration in which a scientist combined two substances in a sealed container and analyzed the results. The ending substances did not look the same as the starting substances.

Samira was given a diagram with the repeating groups of atoms that make up the starting substances, plus information about the properties of the starting and ending substances. She created a model of the repeating groups of atoms that might make up the two ending substances.

A.) Does her model correctly show why the properties of the ending substances are different from the properties of the starting substances?

B.) Describe what could be correct or incorrect about her model

Look at the diagram below then write your answer to question 13 part "A" and "B".

Consider the two electron arrangements for neutral atoms a and b. are atoms a and b the same element? a - 1s2, 2s2, 2p6, 3s1 b - 1s2, 2s2, 2p6, 5s1

Which explanation is true about what happens to a ray of light when it strikes a mirror? a. a light ray is transmitted toward a mirror at a certain angle. the light ray is then reflected by the mirror at an equal angle but in the opposite direction of the transmitted ray. b. an incident ray strikes a mirror at an angle with a line perpendicular to the mirror. the light ray is then reflected at an angle equal to the angle of incidence but on the opposite side of the perpendicular line. c. a reflecting ray strikes a mirror at an angle with a line perpendicular to the mirror. the light ray is then refracted at an angle equal to the angle of the reflecting ray and on the same side of the perpendicular line. d. an incident ray strikes a mirror at an angle with a line parallel to the mirror. the light ray is then transmitted at an angle equal to the angle of incidence but on the opposite side of the parallel line. you so much! : -d take the time to try and answer correctly.

Ammonia and oxygen react to form nitrogen monoxide and water, like this: 4nh3 (g) + 5o2 (g) → 4no (g) + 6h2o (g) also, a chemist finds that at a certain temperature the equilibrium mixture of ammonia, oxygen, nitrogen monoxide, and water has the following composition: compound pressure at equilibrium nh3 65.1atm o2 31.3atm no 62.7atm h2o 65.8atm compound pressure at equilibrium nh3 65.3 atm o2 7.79 atm no 12.1 atm h2o 65.8 atm calculate the value of the equilibrium constant kp for this reaction. round your answer to 2 significant