Gold is alloyed(mixed) with other metals to increase its hardness in making jewelry. (A) Consider a piece of gold jewelry that weighs 9.85 g and has a volume of 0.675 cm3. The jewelry contains only gold and silver, which have densities of 19.3 g/cm3 and 10.5 g/cm3, repectively. If the total volume of the jewelry is the sum of the volumes of the gold and silver that it contains. Calculate the percentage of gold(by mass) in the jewelry. (B) The relative amount of gold in an alloy is commonly expressed in units of karats.
gulmohar Chemistry 1 0
Which of the following is true statement about isotopes?. . A.. The number of protons always equals the number of neutrons in all isotopes.. . B.. The number of protons never equals the number of neutrons in an isotope.. . C.. Different isotopes for the same element will always have the same numbers of neutrons.. . D.. Different isotopes for the same element always have the same number of protons..
baee977 Chemistry 1 0
What is true of elements in a period on the periodic table?. (Points : 3). They have different properties that repeat across the next period.. . They have similar properties that repeat across the next period.. . They have similar names.. . They have different properties that show no pattern.
2580Jason Chemistry 1 0
Allen is carrying out reactions in a lab. One of the products in all reactions is found to be either a precipitate, a gas, or water. What is common between all these reactions? Select one of the options below as your answer:A. They are all decomposition reactions. B. They are all combination reactions. C. They are all combustion reactions. D. They are all single-replacement reactions. E. They are all double-replacement reactions.
Karp660 Chemistry 1 0