Chapter 2: Q. 2.1 P (page 81)
What is the key difference between an element and a compound?
An element is made up of the same type of atoms while a compound is formed by combining different elements in a fixed ratio.
Over 30 million students worldwide already upgrade their learning with Vaia!
All the tools & learning materials you need for study success - in one app.
Get started for free
Chlorine has two naturally occurring isotopes, 35Cl and 37Cl. What is the mass number of each isotope? How many protons, neutrons, and electrons are present in each?
Why was it necessary for separation techniques and methods of chemical analysis to be developed before the laws of definite composition and multiple proportions could be formulated?
Samples of illicit “street” drugs often contain an inactive component, such as ascorbic acid (vitamin C). After obtaining a sample of cocaine, government chemists calculate the mass of vitamin C per gram of drug sample, and use it to track the drug’s distribution. For example, if different samples of cocaine obtained on the streets of New York, Los Angeles, and Paris all contain 0.6384 g of vitamin C per gram of sample, they very likely come from a common source. Do these street samples consist of a compound, element, or mixture? Explain.
State the mass law(s) demonstrated by the following experimental results, and explain your reasoning:
Experiment 1: A student heats 1.00 g of a blue compound and obtains 0.64 g of a white compound and 0.36 g of a colour less gas.
Experiment 2: A second student heats 3.25 g of the same blue compound and obtains 2.08 g of a white compound and 1.17 g of a colour less gas.
Fill in the blanks:
(a) The symbol and atomic number of the heaviest nonradioactive noble gas are ________and ________.
(b) The symbol and group number of the Period 5 transition element whose atoms have the fewest protons are ________and ________.
(c) The elements in Group 6A(16) are sometimes called the chalcogens.The symbol and atomic number of the first metallic chalcogen are ________and ________.
(d) The symbol and number of protons of the Period 4 alkali metal atom are ________and ________.
What do you think about this solution?
We value your feedback to improve our textbook solutions.
