The balanced net ionic equation for precipitation of CaCO3 when aqueous solutions of Li2CO3 and CaCl2 are mixed is

A lab team places 0.250g of an unknown solid acid in an Erlenmeyer flask. They neutralize the solid acid with 15.0ml of 0.210 M

Otrada [13]

Answer:

Molar mass of the unknown acid is 79 grams

Explanation:

We have to first get moles in 15.0 ml of sodium hydroxide solution:

${ \sf{1 \: l \: of \:NaOH \: contains \: 0.210 \: moles }} \\ { \sf{0.015 \: l \: of \: NaOH \: contain \: (0.015 \times 0.210) \: moles }} \\ { \underline{ = 0.00315 \: moles \: of \: NaOH}}$

since mole ratio of acid : base is 1 : 1, so;

moles of acid that reacted is 0.00315 moles of the unknown acid.

then we've to get molar mass:

${ \sf{0.00315 \: moles \: of \: acid \: weigh \: 0.250 \: g}} \\ { \sf{1 \: mole \: of \: acid \: weighs \: ( \frac{1 \times 0.250}{0.00315} ) \: g}} \\ { \underline{ = 79.4 \: g \approx79 \: grams}}$

6 0

3 years ago

Why is Mars visible from earth in the night sky

Studentka2010 [4]

You can see mars in the night sky because it is a very bright planet. Mars is as bright, or brighter than the stars. Yes, all planets are pretty bright, but mars in beyond bright along with jupiter, mercury, etc. Hope this helped! :)

7 0

4 years ago

explain in terms of collision theory, how and why a reactions's rate changes as the reaction progresses

Reptile [31]

The rate of a chemical reaction is the speed with which the reactants are converted to products while the collision theory is used to explain why chemical reactions occur at different rates. It states that for a reaction to proceed, the reactants particles must collide and the more successful collisions there are per unit of time, the faster the reaction will be. As the reaction progresses, the products builds up in the system and the chance that the reactants will collide amongst themselves reduces as the product molecules begin to build up while the molecules of the reactants are deprived. therefore the rate of reaction changes.

3 0

3 years ago

Read 2 more answers

Why is graphite used in pencil lead

ra1l [238]

The bonds between the layers are much weaker than covalent bonds. This enables the layers to slide across each other, making graphite soft. Graphite can also conduct electricity, between the layers of carbon atoms. Graphite is used as pencil 'lead'.

8 0

3 years ago

C12H22O11 + 12O2 ---> 12CO2 + 11H2O

boyakko [2]

Answer:

Oxygen is the limiting reactant.

Explanation:

Based on the reaction:

C₁₂H₂₂O₁₁ + 12O₂ → 12CO₂ + 11H₂O

1 mole of sucrose reacts with 12 moles of oxygen to produce 12 moles of CO₂ and 11 moles of H₂O.

10.0g of sucrose (Molar mass: 342.3g /mol) are:

10.0g C₁₂H₂₂O₁₁ × (1mole / 342.3g) = 0.0292 moles of C₁₂H₂₂O₁₁

And moles of 10.0g of oxygen (Molar mass: 32g/mol) are:

10.0g O₂ × (1mole / 32g) = 0.3125 moles of O₂

For a complete reaction of 0.0292 moles of C₁₂H₂₂O₁₁ you need (knowing 12 moles of oxygen react per mole of sucrose):

0.0292 moles of C₁₂H₂₂O₁₁ × (12 moles O₂ / 1 mole C₁₂H₂₂O₁₁) = 0.3504 moles of O₂

As you have just 0.3125 moles of O₂, oxygen is the limiting reactant.

8 0

4 years ago