🏷️ LIMITED TIME OFFER: GET 20% OFF GRADE+ YEARLY SUBSCRIPTION →

HomeTextbook Notes300,000CA170,000

CHM211H5 Chapter Notes - Chapter 3.1-3.2: Chemical Equation, Hydrochloric Acid, Sodium Chloride

15 views2 pages

14 Oct 2020

School

Department

Course

Professor

Thottackad Radhakrishnan

For unlimited access to Textbook Notes, a Class+ subscription is required.

Document Summary

Chemical reaction: events that describe specific changes in substances. (cid:120) signs of a chemical reaction include the following: colour change, formation of a solid, formation of a gas, heat change (release or absorption of energy, production of light. Chemical equations: a short hand method of describing reactions. Reactants: the substances that enter a chemical reaction (being reacted) Products: substances that are the result of a chemical reaction. The law of conservation of mass/matter: a universal law stating that matter cannot be destroyed, nor can it be created in a chemical reaction. Word equation: short hand description of a reaction using the names of the substances. Example: hydrochloric acid + sodium hydroxide (cid:198) sodium chloride + water. Skeletal/chemical equation: description of a reaction using the chemical formulas of the substances. Example: write the chemical equation and balance the following chemical equation. Carbon dioxide and water react with sunlight to produce oxygen gas and glucose.

Related Documents

CHM211H5 Chapter Notes - Chapter 7: Spectator Ion, Molar Mass, Barium Sulfate

CHM211H5 Lecture Notes - Coefficient Of Variation, Gaussian Function, Standard Deviation

CHM211H5 Chapter Notes - Chapter 5.1-5.3: Chemical Equation, Calcium Carbonate, Limiting Reagent

Related Questions

I need help doing my lab homework, I missed lab that day because, I was sick and it's due.

Chemical Reactions and Equations Learning objectives To observe physical and chemical properties associated with chemical changes To be able to give evidence for the occurrence of a chemical reaction To write a balanced chemical equation To identify areaction as a combination, decomposition, precipitation, single or double replacement, or combustion reaction ntroduction When a substance undergoes a physical change, it changes its appearance but not its composition. For example, when ice melts to form water, it undergoes a physical change from solid to liquid. In a chemical change, the composition of a substance is changed to give a new substance with different physical and chemical properties. For example, when silver tarnishes, the shiny silver (Ag) changes to a dull gray silver sulfide (AgaS). Not only has the chemical formula changed from Ag to Agus, but also the physical properties (shininess) of the substance have changed. Some examples of physical and chemical changes are listed in Table 1 below. Table 1. Comparison of Physical and Chemical Changes Examples of Physical changes Examples and Evidence of Chemical Changes Change in state (melting, freezing, evaporating Formation of a gas (bubbles) subliming) Formation of a solid (precipitate) Change in size Tearing Change in Color Heat is given off or absorbed A solid dissolving in a solvent In a chemical reaction, atoms in the reactants are rearranged to produce new combinations of atoms in the products. However, the total number of atoms of each element in the reactants is equal to the total number of atoms in the products. This is true according to the Law of Conservation of Mass, which states that the total mass remains constant during a chemical reaction. In other words, matter cannot be created or destroyed in a chemical reaction. In a chemical equation, the reactants are shown on the left and the products are on the right. An arrow in between indicates that a chemical reaction occurs. Finally, the physical state of each compound is designated in parentheses after the chemical formula. Solid, liquid, gas, and aqueous (dissolved in water) are shown as(s,(n,(g), and (aq), respectively.

Science Tutor: Chemistry Name: Mixtures, Solutions, &Compounds: Chemical Equations Date Chemical Equations If a chemical symbol can be thought of as a letter and a chemical formula as a word in the language of chemistry, then a chemical equation is a statement or sentence. A chemical equation is a shorthand way of describing a chemical reaction between two or more substances. A "+ sign means "combines with." An arrow points away from the reactants and toward the products (See page 10), and an arrow means "yields." 2Na + Cl2 â 2NaCl means sodium combines with chlorine to yield sodiumn chloride (salt) Look closely at the equation above. Notice the "2" in front of NaCI on the right and Na on the left. That 2, called a coefficient, is necessary to make this equation balance. Remember Antoine Lavoisier? (Page 15) Matter is neither created nor destroyed in a chemical reaction. The same number of each kind of atom must be on both sides of a chemical equation. Because chlorine only exists as a molecule consisting of two chlorine atoms, it requires two atoms of sodium to yield two molecules of salt (NaCI). This illustrates another important law stated clearly by the French chemist Joseph-Louis Proust in 1799. Chemical compounds always combine in certain specific fixed proportions. Wherever sodium and chlorine combine, two atoms of sodium will be necessary to react with one molecule of gaseous chlorine. 1 . For the equation 2Mg + O2â 2MgO + energy: A. List the reactant or reactants 2Hato B. List the product or products C. How many atoms of magnesium does it take to combine with one molecule of oxygen? D. How many molecules of magnesium oxide are produced in this reaction? 2. Hydrogen can combine with oxygen to produce water. We could write the equation like this: H2 + O2 â H2O. But this equation is unbalanced! Rewrite this equation with the correct coefficients so that an atom of oxygen doesn't disappear! (Be careful. If you add a coefficient to one side you may have to adjust the other. Count all the atoms.) 3. Now that you have the idea, balance the following equations: A, Pho, â PbO + 02 C. Ca + H2O â Ca(OH)2 + H2 How is following a recipe to mix up a batch of biscuits (or any other food item) similar to Proust's law for chemical reactions? 4. OMark Twain Media, Inc., Publishers 17

Stoichiometry of a gas producing reaction an getherunactions are mpassive or unchanging qualities. The unchanging reactants together under specific conditions, connect literally atoms, Chemical reactions can be thoug rearranging and new connections (bonds) bei ng made between atoms resulting in the formation o The evolution of a gas reactan process has occurred. Chemical reactions of this kind typican ets with hydrocho converted to products. In this experiment magnesium metai hydrogen gas and a salt. go to completion (all reactants are reacts with hydrochloric acid to form upon combining reactants is considered a clear indication that a chem Rinse a 50 mL Obtain a piece of magnesium metal ribbon graduated cylinder twice with distilled water. y sand remove any oxide by sanding the metal with a light grade sand emove any grit by wiping with a kimwipe, the magnesium metal. The mass should be in the range 0.030 g to 0.035 g. If the mass is ol the metal. Wind the metal into a tight coil which will fit into the mouth too great cut off some graduated cylinder. (not too tight do not want a ball) Insert a long stemmed funnel in the graduated cylinder and pour 4.0 mL (using a 10 mL graduated cylinder) of concentrated hydrochloric acid (12 M) in the bottom of the gradua cylinder. Add a 10 mL portion of distilled water to the graduated cylinder washing dow residual acid. Fill the mixing the water and acid as much as possible. the Avoid graduated cylinder completely to the top with distilled water. beaker of react with the acid in the Place the coil of magnesium in the graduated cylinder. Invert the cylinder into a large water (400- 800 mL) equipped with a thermometer. The metal shoul cylinder producing a gas which is trapped in the cylinder. After all the metal has reacted measure the volume of gas produced. Repeat the procedure. Pre-lab 1. 2. Write the balanced chemical equation. Calculate the volume of gas that can be produced if 0.0750 g of magnesium was reacted with 15.0 mL of 12 M HCI (Pay attention to the limiting reagent) Calculations 3. 4. 5. Calculate the moles of each reactant prior to the start of reaction. (moles of HCl and magnesium) Calculate the moles of gas produced using the limiting reactant and the balanced chemical equation. Use the ideal gas law to calculate the theoretical volume of gas produced based on the limiting reactant and determine the percent error. Lab Report Write a full lab report including Intro, Methods, Results and Conclusion. Be sure to address the following questions in the Conclusion Why is it important not to mix the concentrated HCl and water too much in the graduated cylinder? Why should the mass of magnesium not exceed 0.035 g? (What could happen?) 1) 2)