Wonderful Water 1st activity – Gently bend 4-5 toothpicks. Place in a star formation. Add a few drops of water to the center of the star. With a partner, brainstorm the cause of what happens next.

Water activities 6 Stations scattered around the room. Each station has directions for entire room, but only the materials for one station. No more than 5/group. Each group does each station 2x. 5 minutes for each station. Your job is to read directions, predict what will happen, follow directions, observe what happens, record observations (words and/or pictures.) In some cases, directions are not explicit and you’ll need to create some steps. Graduated Cylinders – use plastic and then glass

Properties of Water Due to two things: Review covalent & ionic bonds Bonding between hydrogen & oxygen atoms Bonding between water molecules Review covalent & ionic bonds Discuss bonds within a water molecule & resulting properties Discuss bonds between water molecules & resulting properties

A covalent bond is formed when two atoms share electrons. Composition of Matter Chapter 2 Compounds Covalent Bonds A covalent bond is formed when two atoms share electrons. Cloud Model

Chapter 2 Covalent Bonding Section 1 Composition of Matter Go to Visual for covalent bonds

Chapter 2 Compounds Ionic Bonds of Matter Ionic Bonds An ionic bond is formed when one atom gives up an electron to another. The positive ion is then attracted to a negative ion to form the ionic bond. Chapter 2 Compounds

Chapter 2 Short Response Standardized Test Prep Short Response Covalent bonding is a sharing of electrons between atoms. Why do some atoms share electrons? Answer: Sharing electrons achieves a stable number of electrons in the orbitals that correspond to the highest energy level for each atom.

Chapter 2 Polarity Water is considered to be a polar Water and Solutions Chapter 2 Space filling model Polarity Water is considered to be a polar molecule due to an uneven distribution of charge. The electrons in a water molecule are shared unevenly between hydrogen and oxygen. Solubility of Water The polarity of water makes it effective at dissolving other polar substances such as sugars, ionic compounds, and some proteins.

Chapter 2 Hydrogen Bonding Section 3 Water and Solutions Chapter 2 Hydrogen Bonding A hydrogen bond is the force of attraction between a hydrogen molecule with a partial positive charge and another atom or molecule with a partial or full negative charge.

Properties from Hydrogen Bonding - Cohesion and Adhesion Section 3 Water and Solutions Chapter 2 Properties from Hydrogen Bonding - Cohesion and Adhesion Cohesion is an attractive force that holds molecules of a single substance together, such as water molecules. Attraction between positive Hydrogen & negative Oxygen charge between water molecules SURFACE TENSION Adhesion is the attractive force between two particles of different substances, such as water molecules and glass molecules. Attraction between positive Hydrogen & negative charge somewhere else CAPILLARY ACTION (CAPILLARITY)

Adhesion / cohesion video on visuals

Chapter 2 Hydrogen Bonding Temperature Moderation Water has the ability to absorb a relatively large amount of energy as heat (high heat carrying capacity) The ability to cool surfaces through evaporation. Density of Ice Solid water is less dense than liquid water due to the shape of the water molecule and hydrogen bonding.

Chapter 2 Standardized Test Prep Multiple Choice 1. The way in which elements bond to form compounds depends on which of the following? A. the model of the atom B. the structural formula of the compound C. the dissociation of the ions in the compound D. the number and arrangement of electrons in the atoms of the elements

Multiple Choice, continued Chapter 2 Standardized Test Prep Multiple Choice, continued The illustration below is a space-filling model of water. Use the model to answer the following question. 7. The covalent bonds on the water molecule depicted in the picture above has partial positive charges on the hydrogen atom and a partial negative charge on the oxygen atom. What do the partial positive and partial negative charges on this water molecule mean? A. Water is an ion. B. Water is a polar molecule. C. Water needs a proton and two electrons to be stable. D. Oxygen atoms and hydrogen atoms have opposite charges.

Which activities showed Water sticking to itself? Water sticking to something else?