Evolution and Adaptation in Science

History of Science

As an example of the changes in ideas of this time, we will examine the behavior of a simple pendulum. Until the 16th century, Aristotle’s theory of pendulums held that the period (the length of time for one swing back and forth), depended on the amplitude (the distance the pendulum swung). We shall now test this idea, just as Galileo did.

A pendulum is a weight hanging from a fixed point by a string or wire which, when pulled back and released, is free to swing in and down due

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Chemical Reaction Rates and Molar Concepts

Reaction Rate

Of a chemical reaction is defined in terms of the time it takes to make a reactant disappear or for a product to appear.

Collinson Theory

Chemical reactions break and form bonds as a result of collision between elemental units of the reactants. Not all cause the breaking or forming of bonds, not all collision are effective. Only collision with sufficient energy and whose molecules have the right orientation may break or form bonds.

Factors That Affect Reaction Rates

  • Temperature: In reactions
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Molar Mass of Solute and Sulfuric Acid Manufacturing Process

An aqueous solution of 2% non-volatile solute exerts a pressure of 1.004 bar at the normal boiling point of the solvent. What is the molar mass of the solute?

Answer

Here,

Vapour pressure of the solution at normal boiling point (p1) = 1.004 bar  (Given)

Vapour pressure of pure water at normal boiling point (p10) = 1.013 bar

Mass of solute, (w2) = 2 g

Mass of solvent (water), (w1) = 100 – 2 = 98 g

Molar mass of solvent (water), (M1) = 18 g mol – 1

According to Raoult’s law,

(p10 – p1p10    =

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Designing a New Sand Filter for a Small Operation: Sizing, Media, and Filtration Methods

The estimated flow rate for this site is 2000 m3/day. The surface overflow rate should exceed 125 m3/m2/d. What will be the surface area of the filter? You can use some leftover Ottawa sand (d10 = 0.00055m) from your last filtration project. How deep should the filter be?

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Let’s make the filter 4 m x 4m.

Depth (L) should be: 1000

So, let L = 1 m; gives us: L/d10 = 1m/0.00055m = 1818 so choose 1m depth.

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* Removal Efficiency = 1 – 0.29 = 0.71 = 71%

Determine the matching sizes (d10) of anthracite (

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Marine Biology Study Guide: Terms and Concepts

Acidic pH – 6

  • Acids are – Can release hydrogen ions

All continental drift – Reefs

  • All types of cells EXCEPT: – Movement

Amino acids – Polypeptides

  • An environment if: – It would be difficult maintain homeostasis

An ex hydrogenous sediment – Manganese nodules

  • An ex class Anthozoa phylum Cnidaria is: – Sea anemone

An example of abiotic factors influencing marine organisms is: – Salinity

  • An ex mutualism – cleaner shrimp

An isopycnal water the density ____ with depth. – Remains the same

  • An ooze is composed of _
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Chromatography: Methods, Phases, and Separation Efficiency

Chromatography:

Physical method of separation. Compounds are distributed between stationary phase and mobile phase – the chromatographic process occurs as a result of repeated equilibration events during the movement of the sample components along the stationary phase bed. The separation occurs due to differences in their affinity for the stationary and mobile phases. As the components exit the system, a detector identifies them based on specific properties of the desired analytes.

Stationary Phase:

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