experimental design and basic chemistry review questions

Experimental Design and Basic Chemistry

Review Questions

Experimental Design

You want to determine the effect of decreasing pH (from acid rain) on trout population in a pond. What is the independent variable and dependent variable?

IV - pH

DV – Trout population

How are inferences connected to observations?

Inferences are conclusions that are based upon observations which are made using the senses.

TRUE or FALSE?TRUE or FALSE?The purpose of a control group is to provide a comparison for the results of the experimental group.

You only have your Reference Section of your Biology Binder. How would you find the number of neutrons in an element?Turn to the Periodic Table and look up the Atomic Mass and Atomic Number then subtract them.

Where are electrons, protons and neutrons found in an atom ?

Electrons are outside the nucleus in the orbitals.

The nucleus contains the protons and neutrons.

Why are valence electrons so great?

They bond!

A.

B.

C.

D.

E.

What are atoms of an element that have a different number of neutrons called?

No such thing

ions

element

nucleus

isotope

What happens when an atom loses electrons?

Positively charged ions are formed when an atom loses electron

What makes ionic and covalent bonds different from each other?Ionic bond – electrons are transferred Covalent bonds - share electrons.

Connection to Water: Ionic compounds will dissolve in

water

TRUE or FALSE?TRUE or FALSE?

Polar covalent bonds are the same a polar bonds.

Solution

Colloid

Suspension

heterogeneous

Solute and solvent

Eventually separates

Match the Mixtures

Compounds are bonded elements in definite proportions whose properties are physically and chemically different than the elements that make them.

What is this compound Ba(Na)₂?

Banana

Write a “word equation” for a neutralization reaction.

Acid + Base Salt + Water

Measurement of H+ ions

High [H+] and low [-OH]

Low [H+] and high [-OH]

pH 1.5 - 3

pH 7.5 – 8.5

intestines

base

pH scale

acid

stomach

All about pH

TRUE or FALSE?TRUE or FALSE?

Buffers are an example of the Characteristic of Life, Metabolism, because the help to maintain appropriate pH ranges.

A.

B.

C.

D.

E.

A polar molecule shares electrons unequally. Because water is polar

It has two oppositely charged ends

It will dissolve lots of stuff

Molecules stick to other charged substances

Molecules stick to each other.

All of the above

Explain cohesion and adhesion in terms of polar attraction.

Cohesion – Negative O- pole is attracted to positive H+ pole

Adhesion – Poles of water will attract to opposite charges of other substances.

Congratulations! You have finished the review.