Which of these statements is true? 1. Electrons reach higher energy levels when they move closer to the nucleus.

2. An electron can absorb energy only from light.

3. The spectrum of hydrogen consists of all frequencies of radiation.

4. The emission spectrum of each element is unique

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.

Use the measurements in the table to determine which unidentified metal has the highest density. metal volume mass a 10.5 cm3 122 g b 14.2 cm3 132 g c 16.1 cm3 115 g d 12.7 cm3 126 g

Which type of intermolecular attractions holds ammonia molecules together with other ammonia molecules?