Chem

What is the total number of electrons that can occupy the d sublevel?

10 electrons.

Which of the following is a reasonable ground-state electron configuration?

1s22s22p5

Calcium (Ca) has an atomic number of 20. What is calcium's ground-state electron configuration?

1s22s22p63s23p64s2

Which of the following is not a possible sublevel?

2d

The partial electron configuration of an atom with 12 electrons is shown.1s22s22p6X Which of the following does X represent?

3s^2

An atom has the following electron configuration. 1s22s22p63s23p4 How many valence electrons does this atom have?

6

What is the wavelength of radio waves that have a frequency of 3.20 x 1010 Hz?

9.38 x 10 −3 m

An electron moved from shell n = 2 to shell n = 1. What most likely happened during the transition?

A photon of energy was released.

When two fluorine atoms bond together in F2, what type of covalent bond do they form?

A single bond, because they overlap orbitals to share one pair of electrons.

Which of the following is a correct formula unit of an ionic compound

Al2O3

In Rutherford's famous experiment, he shot heavy, fast moving, positive alpha particles at a thin gold foil. Based on Thomson's plum pudding model of the atom, what did Rutherford expect to happen, and why?

All the alpha particles would pass straight through the foil because of the even distribution of mass and charge throughout the atom.

A group of students designed a pamphlet. They used images and text to describe the chemical and physical changes that take place during cooking. Which type of scientific model did the students design?

An infographic because the images improve understanding of the changes in matter.

The image compares the arrangement of electrons in two different neutral atoms. A figure labeled Atom Q has a shaded sphere at the center of three concentric circles. The innermost circle has two black spheres. The middle circle has six black spheres. To the left of this figure is another figure labeled Atom P. Atom P has a shaded sphere at the center of three concentric circles. The innermost circle has two black spheres. The middle circle has seven black spheres. Which of the following best explains the position of the two atoms in the periodic table?

Atom P has an estimated Zeff of 7 and is therefore to the right of Atom Q, which has a Zeff of 6.

The table compares the number of electrons in two unknown neutral atoms. Comparison of Electrons Atom Number of Electrons A 2 D 10 Use this information to determine the number of valence electrons in the atoms. Which of the following correctly compares the stability of the two atoms?

Both are unreactive.

The table compares the masses of three unknown subatomic particles. Relative Mass of Particles Particle Relative Mass P 1 Q 0.00054 R 0.99 Which particle is most likely present in the nucleus of the atom?

Both particles P and R.

What is the formula of the compound formed between chlorine (Cl) and calcium (Ca)?

CaCl2, because calcium loses two electrons and chlorine gains one electron.

An atom's Lewis dot structure has four dots. Which of the following elements could it be, and why?

Carbon, because it is in group 14 and has four valence electrons.

Match each element to the number of electrons in its valence shell.

Carbon-4 Hydrogen-1 Magnesium-2 Oxygen-6

Which of the following elements in the third period would you expect to have the most negative electron affinity value, and why?

Chlorine (Cl), because it is a halogen with a high effective nuclear charge.

A scientist calculated the energy required to break bonds in two unknown compounds, A and B. One compound has a covalent bond, and the other has an ionic bond. The table shows a record of these values. Bond Energy Compound A Compound B 769 kJ/mol 432 kJ/mol Based on the table, which of the following statements is true?

Compound B is covalent because sharing of electrons makes relatively weaker bonds.

Which of the following methods can be used to identify the suspected use of heat lamps in a house without entering the house?

Detect the heat emitted by the lamps using infrared rays.

Schrodinger and Heisenberg developed an alternate theory about atomic nature that contradicted some of Bohr's model of the atom. How do changes resulting from new technology and evidence affect the reputation of the atomic theory?

Each time a theory is tested with new evidence, it becomes stronger and more durable.

Modern atomic theory states that atoms are neutral. How is this neutrality achieved?

Equal number of protons and electrons.

Which of the following is most likely to make scientific knowledge stronger?

Evaluating it with experimentation and argument.

What term is used to describe the energy level of any level higher than the ground state of a particle?

Excited state.

Lithium has a 1+ charge, and oxygen has a 2− charge. A Lewis dot diagram should contain one lithium atom and two oxygen atoms to show how these atoms form an ionic bond.

False

A cation is larger than it was as a neutral atom because the added electrons occupy a higher energy level.

False.

Which of the following provides evidence to support Rutherford's model of the atomic nucleus?

Gold foil experiment.

Which of the following groups of elements are likely to have substances that have both metallic and non-metallic properties?

Group 14.

Which of the following properties increase down a column in the periodic table?

Ionic radii

A substance is a good conductor of electricity. Which of the following best explains the probable position of the substance in the periodic table?

It is between groups 1 to 12 because it is a metal.

Using the periodic table, which of the following elements is most likely to have similar properties as calcium, and why?

Magnesium (Mg), because they are both alkaline earth metals

A student observes that an element is shiny, bends easily, and can conduct electricity. What type of element is the student most likely observing?

Metal.

Which type of electromagnetic radiation has a lower frequency than infrared radiation?

Microwaves.

Which of the following correctly compares the radii of Na and Na+?

Na has a larger radius than Na+ because Na+ has lost its outermost energy shell.

What types of atoms typically form covalent bonds?

Nonmetals with nonmetals, because their difference in electronegativity is below 1.7.

What is the formula unit for a compound made from Pb4+ and oxygen

PbO2

A student made the Lewis dot diagram of a compound as shown. What is the error in the Lewis dot diagram?

The Ca atom should transfer only one electron to Cl, and the second electron should be transferred to another Cl atom.

The table shows the number of charged subatomic particles in an ion. Charged Particles Charge on Particle Number of Particles Positive 12 Negative 10 A positively charged substance is brought near the ion. What will most likely happen and why?

The ion will repel the substance because it has lost two electrons.

What is the general trend for electron affinity values going across a period?

The values become more negative.

What is true of neutrons?

They have no charge and are located inside the nucleus.

As you move down group one of the periodic table, what happens to the atomic radii?

They increase, because of the higher number of occupied energy levels.

Which of the following explains how Hahn, Strassman, and Meitner tried to influence the use of their discovery?

They opposed the use of energy released during nuclear fission for military purposes.

Match the scientist to his contribution to the atomic theory.

Thomson: Electrons Rutherford: Nucleus Bohr: Electron Energy Levels

Select the words that correctly fill in the blanks for this statement:

Three, dumbbell.

What is the lowest part of a wave called?

Trough.

A triple covalent bond involves two atoms sharing three pairs of electrons

True

An atom's valence electrons are located in the atom's outermost energy level.

True

The molecule NH3 contains all single bonds.

True

Electrons have been shown to have both wavelike and particle-like properties.

True.

Mendeleev's arrangement of elements in the periodic table was based on the observations and experiments of his predecessors who studied the mass and properties of elements.

True.