EXAM 1 (Chap. 1 - 4) Study Guide Flashcards Preview

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1

 

John Dalton

An English chemist, physicist and meterologist who developed the Atomic Theory:

  • Each element contains indivisible units (atoms).
  • Atoms can be neither created nor destroyed.
  • All atoms of a given element are identical.
  • Atoms of different elements have different masses.

2

 

J.J. Thomson

An English physicist who discovered the electron and came up with the "Plum Pudding Model" of the atom. He also measured the deflection angles of cathode ray particles in a magnetic field. Also:

  • Matter is electrical in nature.
  • Atoms are neutral (both positive and negative).
  • There are electrostatic forces – forces of attraction between unlike charges and forces of repulsion between like charges.
  • Positive charge is evenly distributed throughout the atom.
  • Negative charge is embedded.

3

 

Ernest Rutherford

A British physicist who developed the Nuclear Model of the Atom. 

In 1911, he proved that J.J. Thomson's "plum pudding" model of the atom is incorrect by conducting his own experiment that involved shooting a thin gold foil with alpha particles. 

  • The inner core of the atom (all of the mass) is positively charged.
  • Negatively charged electrons are diffused and outside of the inner core (all of the volume).
  • This model still does not explain the mass of atoms.

4

 

Niels Bohr

A Danish physicist who developed the Bohr Model of the Atom:

  • Electrons are in shells, or specific energy.
  • The closer they are to the nucleus, the lower the potential energy.
  • Electrons can move to different shells, as long as there are vacancies.
  • Electrons absorb photons, increases in energy and moves to a higher energy shell.
  • When the atom has to release extra energy, the electron moves back down a shell and releases a photon (light molecule). This explains the colors in flames.

5

Magnesium has three naturally occurring isotopes:

  • 24Mg (78.99%)
  • 25Mg (10.00%)
  • 26Mg

What is the atomic mass of Mg if the isotopic mass of 25Mg is 24.99 amu, the mass of 24Mg is 23.99 amu, and the mass of 26Mg is 25.99 amu? 

 

24.31 amu

6

 

Which of the following isotopes has the least number of neutrons?

 

59Co           59Ni                 63Cu                 65Zn

 

59Ni

7

 

Is this a physical or chemical property?

A substance is a yellow powder.

 

Physical

8

 

Is this a physical or chemical property?

A substance burns in the air.

 

Chemical

9

 

Is this a physical or chemical property?

A substance has a melting point of 113°C.

 

Physical

10

 

Is this a physical or chemical property?

A substance reacts with zinc (Zn) to form a compound.

 

Chemical

11

 

Is this a physical or chemical property?

A substance has a density of 1.96g/mL.

 

Physical

12

 

Is this a physical or chemical property?

A substance is insoluble in water.

 

Physical

13

 

I want to find out what type of metal my ring is made from. I place it on a scale and find that it weighs 0.0141 lbs.  When I submerge the ring into a cylinder of water, the water level rises from 5.6 mL to 5.9 mL.

What is the mass of the ring in grams (1 lb. = 454 g)?  

 

6.401 g

14

 

I want to find out what type of metal my ring is made from. I place it on a scale and find that it weighs 0.0141 lbs.  When I submerge the ring into a cylinder of water, the water level rises from 5.6 mL to 5.9 mL.

What is the volume of the ring in mL?

 

0.3mL

* 5.9mL – 5.6mL = 0.3mL *

15

 

I want to find out what type of metal my ring is made from. I place it on a scale and find that it weighs 0.0141 lbs.  When I submerge the ring into a cylinder of water, the water level rises from 5.6 mL to 5.9 mL.

What is the density of the ring in g/mL (D = m/v)?

 

21.3 g/mL

* 6.401g / 0.3mL = 21.3 g/mL *

16

 

 

I want to find out what type of metal my ring is made from. I place it on a scale and find that it weighs 0.0141 lbs.  When I submerge the ring into a cylinder of water, the water level rises from 5.6 mL to 5.9 mL.

What is the ring most likely made of?

  • MASS: 6.401 g
  • VOLUME: 0.3 mL
  • DENSITY: 21.3 g/mL

ANSWER: Platinum (Pt)

* The ring is 21.3 g/mL in density. On the periodic table, the element closest to that density is platinum (Pt). *

17

The Ideal Gas Law has two assumptions for a gas to behave ideally. It does not depend on what type of gas we have, but on two other factors (or limitations). List those factors. According to your answer, which of the Noble Gases would behave most ideally?

Ideal Gas Law limitations:

  • Particle size. If particles are too large, the equations break down.
  • Interactions. If there's too much of an attraction, the equations break down.

Helium (He) would behave the most ideally.

 

 

 

18

 

Name the following element:

The smallest Halogen (in diameter)
 

 

Fluorine (F)

19

 

Name the following element:


The smallest Group IIA element (in diameter)
 

 

Beryllium (Be)

20

 

Name the following element:


The smallest period 4 element (in diameter)
 

 

Krypton (Kr)

21

 

Name the following element:


The smallest Transition Metal (assuming the same trends as before) 

 

Zinc (Zn)

22

 

Write the element name and symbol:

The liquid metal
 

 

Mercury (Hg)

23

 

Write the element name and symbol:


The element with 9 protons and 11 neutrons
 

 

20F (Fluorine)

* Start by finding the element with 9 protons, which is Fluorine. Then add the 9 protons to the 11 neutrons to get the new atomic mass of 20. *

24

 

Write the element name and symbol:

The fifth period chalcogen
 

 

Polonium (Po)

25

 

Write the element name and symbol:


The element with atomic number 24

 

Chromium (Cr)

26

 

What is the difference between

mass number, atomic number, and atomic mass?

 

  • MASS NUMBER: Protons + Neutrons
  • ATOMIC NUMBER: Protons
  • ATOMIC MASS: The weighted average of all isotopes of that element

27

 

Classify the following as an element, compound, homogeneous mixture, or

a heterogeneous mixture:

 

A solid bronze statue (bronze is an alloy)

 

 

 

Homogenous Mixture

28

 

Classify the following as an element, compound, homogeneous mixture, or a heterogeneous mixture:

 

A peanut butter and jelly sandwich

 

 

Heterogenous Mixture

29

 

Classify the following as an element, compound, homogeneous mixture, or a heterogeneous mixture:

 

A pure silver ring

 

 

Element

30

 

Classify the following as an element, compound, homogeneous mixture, or a heterogeneous mixture:

 

Baking soda (sodium bicarbonate)

 

 

Compound