Explore BrainMass

Basic Chemistry Problems

This content was STOLEN from BrainMass.com - View the original, and get the already-completed solution here!

Hi, I need some assistance understanding the answers to the following multiple choice questions:

1. The weight of a body varies according to the force of gravity exerted on the body.

2. An anion is the a:
- Positive pole in an electrical system
- Subatomic part of an atom
- Molecule with a +1 net charge
- Negatively charged molecule

3. Determine the number of moles of aluminum in 96.7 g of Al:
- 0.279 mol
- 3.58 mol
- 7.43 mol
- 4.21 mol
- 6.02 ^ 1023 mol

4. The mass of four moles of molecular bromine (Br2) is:
- 80 g
- 320 g
- 640 g
- 140 g
- 24 ^1023 g

5. An irregularly shaped piece of metal with a mass of 114 g was placed into a graduated cylinder that contained 25.00 mL of water. This raised the water level to 42.50 mL. What is the density of the metal?
- 7.25 g/mL
- 6.5 g/mL
- 2.68 g/mL
- 0.592 g/mL

© BrainMass Inc. brainmass.com October 24, 2018, 6:10 pm ad1c9bdddf

Solution Preview

Hello and thank you for posting your questions to Brainmass!
Here are my answers:

1. This is exactly the definition of weight. Weight is the force exerted on an object by gravity.
Reference: http://m-w.com/cgi-bin/dictionary?book=Dictionary&va=weight&x=0&y=0

2. An anion is a ...

Solution Summary

This solution is composed of full explanations to each of the above chemistry-based problems. References are also provided to support the answers. Equations are given in the cases in which they are needed and are supplemented with reasoning as to why the question needed to be approached in that way.

See Also This Related BrainMass Solution

Various Basic Chemistry Problems - Mole, Mass and other Calculations

1) When a mole of C2H4 is combusted it reacts with 3 moles of O2 to produce CO2 and H2O. How many moles of CO2 and how many moles of H2O are produced?

2) What is the mass in grams of 4.25 moles of Mg (NO3)2?

3) The overall reaction producing iron from an ore in a blast furnace is:

Fe2O3 + 3CO --> 2Fe + 3CO2

How many grams of Fe are produced when 275g of Fe2O3 react?

4) Using the bond energy table on page 190 of the text, determine the value of DH for the following reaction:

2F-F + O=O --> 2F-O-F

5) Giving reasons for your answers characterize the following compounds as saturated, or unsaturated, or incapable of existence.

A. CH2 B. C10H22 C. C2H2 D. C2H8 E. C 3H6

6) Determine the empirical formula of the compound that is 87.42% N and 12.58% H by weight.

7) What monomer can be used in an addition polymerization to produce the Polymer Teflon that has a repeating structure as follows:

8) What is the molality of 225g of C6H12O6 in 505 g of H2O?

9) What is the freezing temperature of the solution in question 8?

10) How many joules of energy are needed to raise the temperature of 325.0g of water from 20.0oC to 95.0oC. The specific heat of water is 4.184J/g-oC.

View Full Posting Details