Chapter 1 : Stratosphere

Sunscreens made of ZnO and TiO2 nanoparticles ___ or scatter light

reflect

sunscreens that block UV-B but not UV-A may lead to an increase in ____ skin cancer

melanoma

ozone is only formed in the middle of the stratosphere because the air is ___ which means the ___ molecule concentration is relatively ___ compared to the top of the ___.

also, UV- __ light is relatively less compared to the top of the stratosphere

so __ + O = O3 + heat

denser, oxygen, high, stratosphere

C

O2

Write down mechanism I of ozone destruction by BrO as a pollutant

In the Chapman Mechanism, Which UV lights are required in ‘X’ and ‘Y’ respectively

UV-C, UV-B

why should chemical derivatives be avoided?

it uses additional ___ and ____ waste

reagents, generates

UV light effect on fish include: decreased ____ capacity and impaired ___ development

reproduction, larval

mechanism II does not require atomic ___ and involves __ different starting materials X and X’

oxygen, two

peptide based sunscreen is

1)?

2)?

3)?

non-toxic, biodegradable, environment friendly

UV-B light on the eyes can cause loss of color ___ and eventually ____

vision, blindness

ZnO and Oxybenze sunscreen block which two forms of light?

UV-A and UV-B

Avobenzene only blocks?

UV-B

What are the four factors that affect reaction rates?

• chemical nature of the reactants

• temperature of the reactants

• concentration of the reactants

• the presence of a catalyst

the rate of a reaction ___ with temperature

increases

The rate of a reaction ___ with the concentration of reactants

increases

Collision theory: reactants must ___ in order to react with each other

collide

Postulates of Collision Theory:

1) The rate of the reaction is proportional to the rate of ___ collisions

2) Molecules must be ____ properly when they collide

reactant

oriented

Molecules must have adequate ____ energy to react.

kinetic

In collision theory, the kinetic energy supplied must be high enough to break the ____

chemical bonds

In Collision Theory, molecules with kinetic energies that are too small will ___ each other and ____ (will or won’t) react?

bounce off of each other

won’t