Law of conservation of mass lcm
This presentation is the property of its rightful owner.
Sponsored Links
1 / 26

Law of Conservation of Mass (LCM) PowerPoint PPT Presentation


  • 177 Views
  • Uploaded on
  • Presentation posted in: General

Law of Conservation of Mass (LCM). Law of conservation of mass – states that mass is neither created nor destroyed during chemical reactions or physical changes. Reactant – substance that undergoes a reaction. Product – a new substance formed when reactants undergo chemical change.

Download Presentation

Law of Conservation of Mass (LCM)

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Law of conservation of mass lcm

Law of Conservation of Mass (LCM)


Law of conservation of mass lcm

Law of conservation of mass – states that mass is neither created nor destroyed during chemical reactions or physical changes


Reactant substance that undergoes a reaction

Reactant – substance that undergoes a reaction


Product a new substance formed when reactants undergo chemical change

Product – a new substance formed when reactants undergo chemical change


Law of conservation of mass lcm

Balanced equation - An equation for a chemical reaction in which the number of atoms for each element in the reaction and the total charge are the same for both the reactants and the products. In other words, the mass and the charge are balanced on both sides of the reaction.


Law of conservation of mass lcm

Coefficients – a number placed in front of the parts of a chemical equation to indicate how many are involved ; always a positive whole number.


Subscript

Subscript –


Law of conservation of mass lcm

Formula – a combination of chemical (element) symbols that show what elements make up a compound and the number of atoms of each element


Law of conservation of mass lcm

Chemical equation - A symbolic representation of what happens when chemicals come in contact with one another.  A balanced chemical equation shows how many of what molecules react, how many of what molecules result, and sometimes the state of the substances.


Law of conservation of mass lcm

Demo:

LCM – in chemical reactions, you always end up with the same amount of stuff you start with.

“Stuff” – very scientific could be atoms or mass.


Law of conservation of mass lcm

Demo:

What is the formula for aluminum chloride?

What is the formula for copper chloride?


Law of conservation of mass lcm

Demo:

What will happen if I drop aluminum into a copper chloride solution?


Law of conservation of mass lcm

Demo:

Write the chemical reaction…

CuCl2 + Al → AlCl3 + Cu

Do you notice anything?!


Law of conservation of mass lcm

Demo:

Balance the chemical reaction…

3CuCl2 + Al → AlCl3 + Cu

3CuCl2 + Al → 2AlCl3 + Cu

3CuCl2 + Al → 2AlCl3 + 3Cu

3CuCl2 + 2Al → 2AlCl3 + 3Cu


Law of conservation of mass lcm

__Ca(C2H3O2)2 + __K3PO4__Ca3(PO4)2 + __KC2H3O2Which set of coefficients balances the equation? A. 3, 3, 1, 2B. 6, 1, 1, 3C. 3, 2, 1, 6D. 6, 2, 1, 6

Each answer is on the following slide.


Law of conservation of mass lcm

Which of these would support the idea that mass is conserved in a reaction that produces a gas as a product? A. Heating the reactants to ensure the reaction occurs in a gaseous stateB. Subtracting the mass of the gas from the mass of the solid and liquid productsC. Mixing the reactants and measuring their total mass D. Trapping the gas and measuring its mass

C


Law of conservation of mass lcm

Aluminum metal and oxygen gas combine to produce aluminum oxide (Al2O3). Which of these is the balanced equation for this reaction? A. Al + O2 Al2O3B. 2Al + 2O2 2Al2O3C. 2Al + 3O2 5Al2O3D. 4Al + 3O2 2Al2O3

D


Law of conservation of mass lcm

CaCO3 CaO+ CO2 The chemical equation shows CaCO3 being heated. Which of these statements best describes the mass of the products if 100 g of CaCO3 is heated? A. The difference in the products’ masses is equal to the mass of the CaCO3. B. The sum of the products’ masses is less than the mass of the CaCO3. C. The mass of each product is equal to the mass of the CaCO3.D. The sum of the products’ masses equals the mass of the CaCO3.

D


Law of conservation of mass lcm

Which chemical equation supports the law of conservation of mass? A. 2H2O(l)  H2(g) + O2(g) B. Zn(s) + HCl(aq)  ZnCl2(aq) + H2(g) C. Al4C3(s) + H2O(l)  CH4(g) + Al(OH)3(s) D. CH4(g) + 2O2(g) CO2(g) + 2H2O(g)

D


Law of conservation of mass lcm

2Cu + O22CuO When 127 g of copper reacts with 32 g of oxygen gas to form copper (II) oxide, no copper or oxygen is left over. How much copper (II) oxide is produced? A. 32 gB. 95 gC. 127 gD. 159 g

D


Law of conservation of mass lcm

K + H2O  KOH + H2What is the coefficient for H2O when the above equation is balanced? A. 1 B. 2C. 3D. 4

D


Law of conservation of mass lcm

According to the law of conservation of mass, how much zinc was present in the zinc carbonate? A. 40 gB. 88 gC. 104 gD. 256 g

B


What are the coefficients that will balance this chemical equation a 2 1 1 b 3 4 2 c 2 2 1 d 4 3 2

What are the coefficients that will balance this chemical equation? A. 2, 1, 1B. 3, 4, 2C. 2, 2, 1D. 4, 3, 2

C


Law of conservation of mass lcm

The illustrations show a conservation-of-mass experiment. The solution in the beaker lost mass because _____. A. materials have less mass at high temperaturesB. the mass of the reactants and products was less than 100 gC. sodium sulfate (Na2SO4) is lighter than airD. some of the water molecules turned into gas

C


Law of conservation of mass lcm

D


  • Login