Chemistry Test (2/23/22)

Each arrow shows an electron moving from one energy level to another. Which transitions will release energy?

A. A and D

Which other element is likely to show a similar chemical reaction with oxygen as shown by magnesium, and to which group does it bellong?

A. Ca, it belongs to Group 2

Which pattern(s) may be observed from the arrangement of elements in the periodic table? Select all that apply.

A. Increase number of protons B. similarity in the number of their valence electrons C.similarity in their physical and chemical properties

Which of the following statements about the element from which the ribbon was made, are true? Select all that apply.

A. It has two valence electrons. C. It belongs to the third period.

Identify all of the items that represent an element and not a molecule. Select all that apply

A. Ne B. Li F. H

Atom X shows metallic properties. Identify another element that is likely to show similar metallic properties. Justify your answer.

Any element in group 1 (choose one); b/C it is in group 1 on the periodic table

An atom of bromine has 35 electrons. These electrons are present in energy shells around the nucleus. What is the electron configuration of bromine?

B. 2, 8, 18, 7

Based on the electron configuration of each atom, what is the number of valence electrons for each atom?

B. Atom X = 1; Atom Y = 7

Based on the periodic table, which other element is likely to share common properties with sodium, or Na?

B. Cs

Oxygen reacts with many different elements to form different molecules. As the energy of matter changes, substances experience changes in their states of matter. Choose the two molecules from the list below that contain the greatest kinetic energy.

B. SiO2 (g) D. CO (g)

Based on the electron configuration of Atom Y, to which group in the periodic table does it belong?

C. 17

Which of the following statements about the properties of elements related to an atomic emission spectrum are true? Select all that apply.

C. The light that an element emits is made up of a limited number of narrow lines of light that produce a unique pattern or atomic emissions spectrum for that element. F. An atomic emission spectrum shows the pattern formed when light emitted by an element is separated into its different component wavelengths.

A chemistry graduate student is very skilled at analyzing atomic emission spectra. The printout of her spectrum is printed in black and white. Therefore she has to rely on comparing the widths and positions of spectral lines during analysis. Observe the various atomic emission spectra.

D. Copper

Which of the following is a characteristic of the Group 14 elements?

D. They have 4 valence electrons.

The reaction between Atom X and Afom Y in its gaseous state is usually done in a glass beaker lined with sand. This prevents the glass from cracking as a great amount of energy is released in the form of heat and light during the reaction. Explain if similar precautions need to be followed for the reaction between potassium and Atom Y in its gaseous state.

Similar actions must be taken not only as also in group 1, but as potassium has lesser electro negativity thus creating a stronger ionic bond which will release more energy