FLVS Chemistry Module 2 Notes (w/ Flashcards)

What evidence from J.J. Thomson's experiments with the cathode ray led to the plum pudding model of the atom?

The beam was attracted to a positive charge and repelled by a negative charge, showing that atoms contain small, negatively charged particles.

What is true when an ion is formed?

There is an unequal number of electrons and protons.

Chadwick worked to isolate the neutral particle Rutherford had proposed.

True

What is true of electrons?

They are negatively charged and located outside the nucleus.

Match the scientist to his contribution to the atomic theory.

Match	Term	Definition
	Rutherford	A) Electron cloud and orbitals
	Dalton	B) Nucleus
	Schrodinger	C) Law of Multiple Proportions

1. B

2. C

3. A

The modern atomic theory has been updated over the years as new observations of the atom have been made. What do these changes say about the strength of the modern atomic theory?

 The changes make the theory stronger because it has been tested and edited multiple times, making it more durable.

The nucleus being filled with positively charged particles was hypothesized by Rutherford. When was this discovered in relation to other scientist's atomic hypotheses?

After Thomson but before Chadwick

Nickel has the chemical symbol Ni and the atomic number 28. How many protons, neutrons, and electrons would be found in an atom of nickel-78?

28 protons, 50 neutrons, 28 electrons

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

Use the periodic table to match each of the following element symbols to its name, atomic mass, or atomic number.

Match	Term	Definition
	Sn	A) Tin
	Se	B) 16 (atomic number)
	S	C) 78.971 u (atomic mass)

1. A

2. C

3. B

An atom has atomic number 5 and mass number 11. How many protons does the atom have?

5

Mendeleev's periodic table shocked the scientific community because it contradicted earlier findings about element mass and properties.

False

Helium (He), oxygen (O), carbon (C) fluorine (F), and chlorine (Cl) are all nonmetals. Using the periodic table, which pair of nonmetals do you predict has the most similar properties, and why?

Fluorine and chlorine, because they are both halogens

The image shows the representation of an unknown element in the periodic table.



Based on the representation, which of the following statements about the element is true?

The sum of the masses of protons and neutrons is 20.1797.

The diagram shows four different locations in an atom.



Which locations are likely to have subatomic particles that are constantly in motion?

2 and 4

Magnesium (Mg) has an atomic number of 12. What is the electron configuration of magnesium?

1s²2s²2p⁶3s²

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

6 electrons

Which of the following is a reasonable electron configuration?

 1s²2s²2p⁶

The following orbital notation is for which element?

N

Which of the following is not a possible sublevel?

3f

What type of orbital is dumbbell-shaped?

p oribital

The partial electron configuration of an atom with 14 electrons is shown.

1s²2s² 2p⁶3s²X

Which of the following does X represent?

3p²

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

9.38 x 10⁻³ m

Energy has both wavelike and particle-like properties, but electrons have only particle-like properties.

False

Compared to visible light, an electromagnetic wave that has a longer wavelength will also have ________.

lower frequency and equal speed

Which type of electromagnetic radiation has a shorter wavelength than ultraviolet light?

X-rays

Match each type of electromagnetic radiation to its description.

Match	Term	Definition
	Heat from warm objects, used to detect the location of objects	A) Visible light
	Low-energy radiation used to transmit signals such as television and cellular phone	B) Radio waves
	Given off by very hot objects, such as the sun	C) Ultraviolet light
	All the radiation humans can see, ranging from red to violet	D) Infrared radiation

1. D

2. B

3. C

4. A

Where are the most reactive metals located?

 Lower left of periodic table

Which element in the third period would you expect to have the larger atomic radius, sodium (Na) or Sulfur (S)?

 Sodium because it has fewer protons attracting electrons in the same energy levels.

Which of the following elements would you expect to have the lowest ionization energy value, and why?

Lithium (Li), because it has a low effective nuclear charge and large radius

Use these two constants for the question that follows:

• e = 1.6 × 10⁻¹⁹ C

• k = 8.99 × 10⁹ N m²/C²

Two positive charges are 10⁻¹⁶m away from each other. Using Coulomb's law, which of the following is the electrical force between these two particles?

 23,000 N

The effective nuclear charge is the sum of all forces on electrons by the positively charged nucleus.

False