(will give brainliest!! please help me! thank you!) a) The rows on the periodic table are called periods. How many energy levels are in the atoms of each element in period 2 (lithium-neon)

b) What is the group number of the halogens?

c) What do the elements in each group have in common?

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Base your answer on the information below and on your knowledge of chemistry. nitrogen dioxide, no2, is a dark brown gas that is used to make nitric acid and to bleach flour. nitrogen dioxide has a boiling point of 294 k at 101.3 kpa. in a rigid cylinder with a movable piston, nitrogen dioxide can be in equilibrium with colorless dinitrogen tetroxide, n2o4. this equilibrium is represented by the equation below. 2no2(g) n2o4(g) + 58kj at standard pressure, compare the strength of intermolecular forces in no2(g) to the strength of intermolecular forces in n2(g).

Acontainer holds 35.8 moles of gas under 10.0 atm of pressure at 70.0 c. what is the volume of the container?

If 90.0 grams of ethane reacted with excess chlorine,how many grams of dicarbon hexachloride would form