Chapter 2, Problem 2.92E

Give the complete symbol (XZA), including atomic number and mass number, of (a) a nickel atom with 31 neutrons, and (b) a tungsten atom with 110 neutrons.

2.74 The accompanying table provides the identity of the two naturally occurring isotopes for four elements and the atomic weights for those elements. (In each case, the two isotopes differ in mass number by two.) Which element has the mass spectrum shown? Explain your answer.

Give the complete symbol(ZAX), including atomic number and mass number, of (a) a nickel atom with 31 neutrons, (b) a plutonium atom with 150 neutrons, and (c) a tungsten atom with 110 neutrons.

The following table gives the number of protons and neutrons in the nuclei of various atoms. Which atom is the isotope of atom A? Which atom has the same mass number as atom A? Protons Neutrons Atom A 32 39 Atom B 33 38 Atom C 38 50 Atom D 32 38

The mass-to-charge ratio for the positive ion F+ is 1.97 107 kg/C. Using the value of 1.602 1019 C for the charge on the ion, calculate the mass of the fluorine atom. (The mass of the electron is negligible compared with that of the ion, so the ion mass is essentially the atomic weight.)

In a hypothetical universe, an oil-drop experiment gave the following measurements of charges on oil drops: 5.55 1019 C, 9.25 1019 C, 1.11 1018 C, and 1.48 1018 C. Assume that the smallest difference in charge equals the unit of negative charge in this universe. What is the value of this unit of charge? How many units of excess negative charge are there on each oil drop?

From the following written description, write the balanced chemical equation for the reaction including state symbols. A diatomic gaseous molecule that contains 17 protons per atom is reacted with a solid element that has an atomic number of 19 to yield an ionic compound.

A single molecule has a mass of 7.31 1023 g. Provide an example of a real molecule that can have this mass. Assume the elements that make up the molecule are made of light isotopes where the number of protons equals the number of neutrons in the nucleus of each element.

Using the information in Table 2.1, answer the following questions. In an ion with an unknown charge, the total mass of all the electrons was determined to be 2.55 1026 g. while the total mass of its protons was 5.34 1023 g. What is the identity and charge of this ion? What is the symbol and mass number of a neutral atom whose total mass of its electrons is 3.92 1026 g, while its neutrons have a mass of 9.35 1023 g?