Chemistry

1) Explain how you can take the mass of a substance, such as salt on the electronic balance without pouring the salt directly on the balance. (Be specific in your answer).

1) J.J. is found to be 6’4” is an example of which type of measurement. 2) Give an example of an inference. An experiment is being completed to determine which type of light bulb will burn the longest. 3) Determine the dependent variable in the experiment.

Use the following information to answer questions 1-4. Which type of sod grows the best in Georgia weather? A study is completed to determine the above question. Three types of sod is studied over a course of 2 years. The type of soil used is the same, the same type of lawn care is completed, and they are all in the same type of environment. One lawn was left with only dirt for the yard for the 2 year period. 1) Determine the independent variable. 2) What is the dependent variable? 3) What is the control in the experiment?

1) We do a lab on a substance that has a boiling point of ˚C. We completed four trials on the boiling point of the substance and got results of ˚C, ˚C, ˚C, and ˚C. Are our results precise, accurate, both, or neither? 2) Explain how a scientific theory and scientific law are different. 3) How should acid and water be mixed together?

Morgan and Kayla want to find out which brand of women’s deodorant is the most effective when working out. They have 4 groups set up for the experiment. All of the groups complete the same workout, have the same number of women in each group, and workout for the same length of time. Group 1 uses Secret, Group 2 uses no deodorant, Group 3 uses Dove, and Group 4 uses Lady Speed Stick. 1) What is the control. 2) Name a constant. 3) What is the independent variable? 4) What is the dependent variable?

Research is completed to see which type of battery lasts the longest. Five different brands of batteries are tested. The batteries were used in the same type of objects (toys, flashlights, razors, etc.), and used the same duration of time. 1) What is the independent variable? 2) Explain how you would solve the number of meters in a 1.60 km race.

1) A cell found in the human body is found to have a diameter of um. What is the diameter of the cell in m. 2) The track at school is 0.40 kilometers long. Determine the length of the track in miles.

1) How many cups of Kool-Aid are in 21, mL? 2) Determine the number of km it is to Hiram (Hiram is miles from Rockmart).

1) We look up the density of copper on the Internet and find the density to be 8.92 g/mL. During a lab, Evan and Jay find the density of a piece of copper to be 6.35 g/mL. Determine the percentage error of their findings.

1) An object is found to have a melting point of ºC during an activity. Determine the percentage error of the measurement if the textbook had the object’s melting point to be ºC. 2) A steak is grams. How many ounces is the steak? 3) Determine the temperature in Celsius of a microorganism that has a temperature of Kelvin.

1) In a lab, we take the temperature of salt water. We find the temperature of the water to be ºC. What is the temperature of the water in Fahrenheit? Use the following scenario to answer questions 2-3. Tyler wants to know which kicking position produces the most power when kicking field goals. 2) What is the dependent variable? 3) Determine the independent variable.

1) In a lab, McKayla and Johnna find the atomic mass of potassium to be 30.00, 38.00, and The atomic mass of potassium found in the book is Are McKayla and Johnna precise, accurate, both or neither? 2) The average atomic mass for McKayla and Johnna is What is the percentage error of the measurement if the actual atomic mass is 39.10? 3) The football field is yards in length. Determine the length of the field in miles.

1) Determine the number of mm in km. 2) How many kilometers are in 4, feet? 3) An experiment is completed to see which brand of running shoe lasts the longest when exercising. What is the independent variable?

1) Which subatomic particle has a relative mass of 0? (Proton, Neutron, Electron) 2) Explain how you can determine an element’s atomic number. 3) How many L are in 50 mL?

A study is completed to find out which grade (87, 89, 93) of gasoline allows a car to perform most effectively over time. Miles driven in the cars, environmental conditions, how the cars were driven, and maintenance of the cars all remained the same. 1) Determine the independent variable in the study. 2) What is the dependent variable? 3) Name a constant. 4) How many meters are in 756,850 mm?

1) Which area (nucleus or electron cloud) encompasses the largest volume of an atom? 2) Which subatomic particle is the least massive? 3) Why can’t the number of protons of an element ever change? 4) Give an example of a qualitative measurement.

1) If Iodine has an atomic number of 53 and 72 neutrons. Determine the mass number of Iodine. 2) Find the number of neutrons an atom of Rhodium has if it has a mass number of ) Iridium has 114 neutrons and a charge of 2. What is the element’s mass number? How many electrons does the element have?

1) An element of Magnesium loses 1 electron and it has a mass number of 25 and 13 neutrons. Determine the charge of Magnesium. 2) What changes in an atom of an element to make it become charged? 3) If an element has a mass number of 39, 20 protons, and a charge of 2. How many neutrons does the element have? Determine the electrons the element has? Name the element.

1) List as many relevant, distinct facts as you can about the following isotope Sr 2

1) What is the mass number of the element? 2) An unknown element has two isotopes with atomic masses and percent abundances of 6.00 (7.50%) and 7.00 (92.50%). What is the name of the element?

1) If a neutral atom gains 3 neutrons and loses 3 electrons, is the atom neutral, positive, or negative? 2) The following 2 atoms represent ____________________. N-14 N-15 3) Which of the following changes in the isotopes of an element? (Mass Number, Atomic Number, Neutrons, Protons)

1) An unknown element has 3 stable isotopes with atomic masses and percent abundances of the following: 1) and %, 2) and 0.037%, 3) and 0.204%. Determine the average atomic mass of the element and name the element. 2) Three isotopes of Sodium are Na-22, Na-23, and Na-24. Which isotope of Sodium is the most abundant in nature? Why?

1) An atom of Carbon has 7 neutrons and 4 electrons. What is the mass number of Carbon? Determine the charge on Carbon. If it has a charge, what is this charged particle called? (Cation or Anion) 2) Which subatomic particle has a mass of 1 and a charge of 0? 3) Where is most of the volume found in an atom? (Nucleus, outside the atom, electron cloud)

For the following 5 questions, state whether each characteristic is ionic or covalent. 1) Shares electrons 2) Occurs between metals and nonmetals 3) Normally soluble in water, but not nonpolar liquids 4) Will not conduct an electrical current 5) High Melting Point 6) Compare and contrast the following: Ca-39 and Ca-40 7) Where are the metals located on the periodic table?

1) An ion of an element has 62 neutrons, 46 electrons, and a charge of 2. Determine the identity of the element. 2) How are ionic and covalent compounds different?

1) How are ionic bonds formed? (Make sure you discuss how the electrons move) 2) How does an atom become as stable as possible? 3) The force that holds 2 atoms together is called ______________. 4) How are covalent bonds formed? 5) Draw an example of a covalent bond.

1) Draw the electron dot structure for Helium. 2) What group or family contains elements with 5 valence electrons? 3) Which group/groups of elements is/are the most similar? A) Helium and Magnesium B) Fluorine and Iodine C) Hydrogen and Helium D) Carbon and Aluminum Se-78 has a charge of -2. Answer the following questions using this information. 4) How many electrons does the atom have? 5) Determine the number of neutrons. 6) Se-78 represents a/an ______________________.

1) Which subatomic particle is involved in the bonding of atoms? (Proton, Electron, Neutron) 2) Write the chemical formula for Aluminum Phosphide. 3) We are going to combine Magnesium and Neon. What is the formula for this compound? 4) Determine the name for the following chemical formula: Ca 3 N 2

Classify the following compound as ionic or covalent. 1) C 3 H 8 2) When writing ionic compounds, which should always being written first: (Metal or Nonmetal) 3) Write the name for the following compound: SrCl 2 4) Determine the chemical formula for the compound that forms when oxygen reacts with aluminum.