Chapter 2 Antacids Why do we need antacids

Chapter 2: Antacids

Why do we need antacids? l Your body needs hydrochloric acid to digest food. l Too much acid can cause heartburn and ulcers and can damage your esophagus.

Antacids versus Acid Inhibitors There are two types of medicines you can use Antacids Acid Inhibitors Neutralizes the acid currently in your system Controls the production of acid in your body Work quickly but your body can make more acid again Long-term solution, but needs to build up in your system to be most effective Alka-Seltzer ®, Rolaids ®, Tums ®, Malox ®, Mylanta ® Tagamat ®, Zantac ®, Pepcid AC ® Is it fair when a commercial compares the fast action of an antacid to an acid inhibitor that takes up to 7 days to build up?

Section 2. 1—Types of Matter Objectives • Define and distinguish between pure substances and mixtures

Classification of Matter Pure Substances Element Compound Mixtures Homogeneous (Solutions) Heterogeneous

Matter l Matter is defined as anything that has mass and takes up space. l It is classified as either a pure substance or a mixture

Pure Substances versus Mixtures Matter Pure Substances Mixtures Every piece of matter is exactly the same More than one type of substance mixed together

Elements versus Compounds Pure substances are either elements or compounds. Elements Compound Every atom is the same type of atom More than one type of atom chemically bonded together. Every molecule is the same.

Elements Single Atom Element Cannot be broken down by chemical or physical processes to form anything else! • A pure substance! • Every atom is the same type. • Elements can be found on the periodic table.

Compounds Single Molecule Made of more than one type of atom (that is, more than 1 element) bonded together. Compound • A pure substance! • Every molecule of a compound is the same. Can be broken down into its elements by chemical reactions only

Mixtures can be classified as homogeneous or heterogeneous. Homogeneous Heterogeneous • It looks the same throughout • Also called a solution. Different matter can be seen (chunks, bubbles, floaties, layers, etc. )

Mixtures More than 1 type of pure substance Mixture • Not a pure substance! • A physical combination – no chemical bonds between substances Can be separated through physical means – a chemical reaction is NOT necessary.

Mixture possibilities l Mixtures can be any combination of solids, liquids and gases: ¡Solid-solid: medicine tablet, alloy. ¡Solid-gas: smog ¡Solid-liquid: salt water ¡Liquid-liquid: lemon water, vinegar. ¡Gas-Liquid: carbonated water, sea water. ¡Gas-Gas: air

True solutions, Colloids & Suspensions True Solution Colloid Suspension Particles don’t settle out and are too small to scatter light Particles don’t settle out but are large enough to scatter light Particles will settle out over time Dissolved Particle Size Increases

Particles Scattering Light l If the dissolved particles are large enough to scatter light, we say it exhibits the “Tyndall Effect” Solution Light passes through unchanged Colloids exhibit the Tyndall Effect Light is scattered by larger solute particles

Connect these concepts with Antacids l What type of matter do you think antacids are? ¡Pure substance (Element or compound) ¡Mixture (homogeneous or heterogeneous)

Connect these concepts with Antacids l Antacids are mixtures. l They contain active & inactive ingredients l What purposes could the inactive ingredients serve?

Connect these concepts with Antacids l Inactive ingredients might ¡Add enough volume to make the pill able to be handeled ¡Add color ¡Add flavor ¡Allow the tablet to be compressed and formed

Let’s Practice Example: Determine if each is element, compound, homogeneous or heterogeneous mixtures Tin foil Copper pipe Concrete Carbon tetrachloride Sports drink

Let’s Practice Example: Determine if each is element, compound, homogeneous or heterogeneous mixtures Tin foil Element Copper pipe Element Concrete Heterogeneous mix Carbon tetrachloride Compound Sports drink Homogenous mix

Physical Separation of Mixtures l Substances in a mixture are separated by physical processes. These are based on differences in the physical properties of the substances. 1. Manual separation is used to separate substances based on differences in color, shape, or size. 2. Siphoning is used to separate oil & water. Oil & water can be separated because of differences in density.

Physical Separation of Mixtures (cont. ) 3. Using a magnet can separate out metals that are attracted to a magnet. 4. Substances, like table salt, that are soluble in water can be separated from other solids (for example, sand) by simply making a solution.

Physical Separation of Mixtures (cont. ) 5. Filtration uses a screen or filter (any porous barrier) to separate the differently-sized substances in a heterogeneous mixture. Smaller particles (like slat and water) will pass through but larger ones (like the sand) will be trapped by a filter.

Physical Separation of Mixtures 6. The salt can then be separated from the water by distillation. Distillation is a technique that separates the components of solutions based on differences in their boiling points.

Physical Separation of Mixtures (cont. ) 7. In paper chromatography, a mixture of substances will separate out on paper primarily due to the tendency of each to be attracted to and travel across the surface of another material.

Physical Separation of Mixtures 8. Crystallization is a separation technique for solutions that results in the formation of pure solid particles from a solution containing the dissolved substance. In rock candy, for example, as water evaporates from a sugar water solution, the solution becomes more concentrated. The amount of water present cannot keep all the sugar in the solution dissolved. The sugar therefore crystallizes on the string.