Flashcards
Science Test Nov 30th 2017
Cards in this deck (13)
- 1What are the methods of measuring concentration?- Mass percent (%m/m)
- Volume percent (%V/V)
- Mass/volume percent (%m/V)
- ppm
- Grams per Litre
- Moles per Litre - 2How do you calculate mass percent concentration and volume percent concentration?
- 3How do you calculate mass/volume percent?g of solute
--------------- x 100
ml of solution - 4How do you calculate ppm?Make a ratio with:
1
----------
1,000,000 - 5How do you calculate grams per litre?grams of solute
-----------------------
litres of solution - 6How do you calculate moles per litre?moles of solute
------------------------
litres of solution - 7What is the formula for diluting a solution?C1 X V1 = C2 X V2
- 8What are the steps to making a solution and diluting it?Solution:
1- In a small 50 ml beaker, measure 3.68 g of potassium dichromate.
2- Add distilled water to the volumetric flask (about halfway up the larger part of the flask).
3- Using a funnel, put the potassium dichromate into the 250ml volumetric flask.
4- “Mix” the flask to dissolve the potassium dichromate in the solvent.
5- Add more dissolved water until the meniscus approaches the line on the volumetric flask.
6- Start using a pipette for precision and be sure the lowest point on the meniscus touches the line.
Dilution:
1- Measure 10mL of your solution in a graduated cylinder.
2- Add this measured solution to a 100mL volumetric flask
3- Add distilled water to the volumetric flask until the bottom of the meniscus approaches the line on the volumetric flask.
4- Start using a pipette for precision and once again, be sure that the lowest point on the meniscus touches the line on the volumetric flask. - 9How can a neutralization rection be noticed?1. Formula = ACID + BASE = SALT + WATER
2. When an acid is added a base to make the solution neutral - 10What is an electrolyte?Water solutions that conduct an electric current
- 11What is a non-electrolyte?It does not contain charges or ions and so can never conduct electricity.
Covalent compounds are always non-electrolytes. - 12What are strong and weak electrolytes?A strong electrolyte is an ionic compound where almost all the molecules dissolved in water separate into ions. Many ions are released and the current flows easily.
- 13—
Information
- Description
- Flashcards on Science Test Nov 30th 2017, created by Halie Mei Jensen on 30/11/2017.
- Created by
- Halie Mei Jensen
- Views
- 0
- Rating