# Noble gases halogens alkaline earth metals alkali

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noble gases. halogens. alkaline earth metals. alkali metals. none of the above noble gases. halogens. alkaline earth metals. alkali metals. none of the above noble gases. halogens. alkaline earth metals. alkali metals. none of the above
6/27/2021 06_Chap04 Part A Which of the following pairs of elements do you expect to be most similar?
11/13 Correct Chapter 4 Question 54 - Multiple Choice
Correct Chapter 4 Question 42 - Multiple Choice Part A How many protons and electrons are present in O ? ANSWER: and and and and and
Correct Chapter 4 Question 46 - Multiple Choice Part A What is the charge on the ion formed by aluminum?
6/27/2021 06_Chap04 Part A What is the mass number of the hydrogen isotope that contains 2 neutrons? ANSWER: ANSWER: 1 4 2 3 none of the above Correct Atomic Number and Mass Number Learning Goal: To understand the relationship between atomic number and mass number. Atoms are described by an atomic number and a mass number. The atomic number is the number of protons in the nucleus. The mass number represents the sum of the protons and the neutrons in the nucleus. If the number of negative electrons is equal to the number of positive protons, then the atom is neutral. If the number of protons and electrons are not equal, then the atom will have a charge. For example, a phosphorus ion with 15 protons, 17 neutrons, and 18 electrons would have an atomic number of 15, a mass number of 32, and a charge of 3. Part A What is the mass number of an ion with 106 electrons, 157 neutrons, and a +1 charge? Express your answer as an integer. Hint 1. Determine the number of protons How many protons does this ion have? Express your answer as an integer. Hint 1. How to approach the problem A +1 charge means that the number of protons exceeds the number of electrons by one. ANSWER: Hint 2. Define mass number Which of the following is equal to the mass number? ANSWER: 107
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6/27/2021 06_Chap04 Correct Chapter 4 Question 57 - Multiple Choice Part A An atom of a carbon-14 isotope would contain: 264
13/13 Correct Score Summary: Your score on this assignment is 82.2%. You received 12.33 out of a possible total of 15 points.
Correct Chapter 4 Question 63 - Multiple Choice Part A A fictional element has two isotopes, each making up 50% of the population. Isotope 1 has a mass of 80.0 amu, Isotope 2 has a mass of 85.0 amu. Calculate the atomic mass of the fictional element. 165 amu 42.5 amu 82.5 amu 40 amu none of the above