Download presentation

1
**Making Molar Solutions**

From Solids

2
**What are molar solutions?**

A molar solution is one that expresses “concentration” in moles per volume Usually the units are in mol/L mol/L can be abbreviated as M or [ ] Molar solutions are prepared using: a balance to weigh moles (as grams) a volumetric flask to measure litres L refers to entire volume, not water! Because the units are mol/L, we can use the equation M = n/L Alternatively, we can use the factor label method

3
**Calculations with molar solutions**

Q: How many moles of NaCl are required to make 7.5 L of a 0.10 M solution? M=n/L, n = 0.10 M x 7.5 L = 0.75 mol # mol NaCl = 7.5 L x 0.10 mol NaCl 1 L = 0.75 mol But in the lab we weigh grams not moles, so … Q: How many grams of NaCl are required to make 7.5 L of a 0.10 M solution? # g NaCl = 7.5 L x 0.10 mol NaCl 1 L x g NaCl 1 mol NaCl =43.83 g Read pages 288 – Do Q

4
# g NaOH = 3.00 L x mol NaOH 1 L x g NaOH 1 mol NaOH =15.0 g # g NaCl = 5.0 L x 0.56 mol NaCl 1 L x g NaCl 1 mol NaCl = 164 g 355 ppm = 355 mg/L or g/L # g CO2 = 1.00 L x g CO2 1 L =.355 g 0.355 g CO2 x 1 mol CO2 44.0 g CO2 = 8.07 x 10–3 mol 1L = 8.07 x 10–3 mol/L a) 235 g 3000 mL x 100% =7.83 % W/V b) mol/L = 4.02 mol / 3.00 L = 1.34 mol/L

5
**Practice making molar solutions**

Calculate # of grams required to make 100 mL of a 0.10 M solution of NaOH (see above). Get volumetric flask, plastic bottle, 100 mL beaker, eyedropper. Rinse all with tap water. Fill a beaker with distilled water. Pour mL of H2O from beaker into flask. Weigh NaOH. Add it to flask. Do step 5 quickly. Mix (by swirling) until the NaOH is dissolved. Add distilled H2O to just below the colored line. Add distilled H2O to the line using eyedropper. Place solution in a bottle. Place label (tape) on bottle (name, date, chemical, molarity). Place bottle at front. Rinse & return equipment.

6
**More Practice Questions**

For more lessons, visit How many grams of nitric acid are present in 1.0 L of a 1.0 M HNO3 solution? 2. Calculate the number of grams needed to produce 1.00 L of these solutions: a) 1.00 M KNO3 b) 1.85 M H2SO c) 0.67 M KClO3 3. Calculate the # of grams needed to produce each: a) 0.20 L of 1.5 M KCl b) L of M HCl c) 0.20 L of 0.09 mol/L AgNO3 d) 250 mL of 3.1 mol/L BaCl2 4. Give the molarity of a solution containing 10 g of each solute in 2.5 L of solution: a)H2SO4 b)Ca(OH)2 63 g 101 g 181 g 82 g a) 22 g b) 1.75 g c) 3 g d) 0.16 kg 5. Describe how 100 mL of a 0.10 mol/L NaOH solution would be made. a) mol/L b) mol/L

Similar presentations

Presentation is loading. Please wait....

OK

Entry Task: Nov 21st Block 2

Entry Task: Nov 21st Block 2

© 2018 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Ppt on himalaya in hindi Ppt on us time zones Ppt on public health administration in india Ppt on national education policy 1986 toyota Ppt on strategic brand management Ppt on applied operational research ppt Ppt on business planning process Ppt on different types of dance forms list Ppt on robert frost free download Ppt on asymptotic notation of algorithms definition