Monday, November 4 th, 2013 Characteristics of Matter

Today’s Objectives To differentiate between chemical and physical properties To complete density calculations To understand the chemistry of snake venom!

Today’s Agenda Bell Ringer Revisit last-week’s activity (Density) –Answer questions (Data Analysis and Conclusions) Practice Density Calculations Read About Snake Venom! (Science World)

Bell Ringer Physical Property or Chemical Property? Glass melts at 600°C Carbonic Acid erodes limestone Milk turns sour Coffee helps people stay alert Rubber is flexible Copper conducts electricity Iron is magnetic What do we call the method that Archimedes used to determine the volume of the irregularly shaped ‘gold’ crown? Mass is defined as the amount of ______ out of which an object is formed. Volume is defined as the amount of ______ an object/material occupies. CP PP The Displacement Method matter space

Density Investigation Most groups found the density of both rubber stoppers to be 1.4g/ml. Why would you expect both stoppers to have the same density? Most groups found the density of 1 marble to match the density of 3 marbles (2.5g/ml), why would they be the same? What must the density of the graduated cylinder be? Why? Since they are made out of the same material (rubber) you’d expect them to have the same density. The particles out of which the rubber is formed is packed equally “tight” regardless of the shape or amount of rubber present. Since all the marbles are made out of the same material (glass), you’d expect the density (measure of how tightly packed) to be the same, regardless of how many marbles you have! The density of the graduated cylinder should be approximately 2.5g/ml, because it (like the marbles is made out of glass!

Density Dilemma! 1 st problem solution method: –Write the “given” information: –Choose the correct formula, substitute and solve for the unknown value: –Answer WITH units! Given: m = 18.9g V = 1.12ml D = ? D = m/V m = D x V V = m/D D = 18.9g/1.12ml D = g/ml This ring can NOT be gold!

Science World! Treat these magazines carefully, they’re a class-set that will need to be used by ALL 8 th grade students! Do not write in, or destroy the magazines in any way!

Snake Bite!(p.14,15) 1.To whom is the venom sent to be studied? 2.Name three other types of animals that are venomous. 3.Why do scientists study snake venom? 4.What are poisonous molecules called? 5.How is anti-venom produced? University Researchers, drug companies, and other institutions studying venom. Spiders, scorpions, lizards, insects, fish and even mammals. They’re learning what makes venom so harmful, how to counteract its sometimes- Deadly effects on human victims, and how it can help treat disease. Toxins Small quantities of venom are injected into host organisms (like horses), the Antibodies generated by the host are collected and used as antivenom.

Snake Bite! (p. 16,17) 1.What does the venom of a diamondback rattlesnake do to its victims? 2.What is the process of gathering the venom from snakes called? 3.How does a doctor treat a patient who is unaware of what type of snake bit them? 4.What is the venom from the deadly black mamba used for? 5.What is the only venomous primate?

Enjoy the other “Science World” Articles for the remainder of class Remember: –Treat these magazines carefully, they’re a class-set that will need to be used by ALL 8 th grade students! –Do not write in, or destroy the magazines in any way!