APA citation
Work Ability, Physical Activity, and Cardiorespiratory Fitness: 2-year Results From Project Active
An adequate level of physical activity may maintain or promote work ability in aging workers. Project Active is a randomized trial comparing a Lifestyle physical activity program with a Structured exercise program in sedentaryhttp://journals.lww.com/joem/Abstract/2000/09000/Work_Ability,_Physical_Activity,_and.12.aspx
UC Devis Chemwiki - The Effect of Concentration on Rate of Reaction
For many reactions involving liquids or gases, increasing the concentration of the reactants increases the rate of reaction. In a few cases, increasing the concentration of one of the reactants may have little noticeable effect of the rate. These cases are discussed and explained further down this page. Don't assume that if you double the concentration of one of the reactants that you will double the rate of the reaction. It may happen like that, but the relationship may well be more complicated.
For many reactions involving liquids or gases, increasing the concentration of the reactants increases the rate of reaction. In a few cases, increasing the concentration of one of the reactants may have little noticeable effect of the rate. These cases are discussed and explained further down this page. Don't assume that if you double the concentration of one of the reactants that you will double the rate of the reaction. It may happen like that, but the relationship may well be more complicated.
The Effect of Concentration of Substrate on the Rate of an Enzyme Controlled Reaction - Beverley High School.
If you increase the concentration of the substrate (the chemicals involved) in an enzyme controlled you will speed up the chemical reaction.
he way that changing the concentration of a solution affects the rate of a reaction. Be aware that this is an introductory page only. If you are interested in orders of reaction, you will find separate pages dealing with these. You can access these via the rates of reaction menu
http://www.chemguide.co.uk/physical/basicrates/concentration.html
Additional research
| THE EFFECT OF CONCENTRATION ON REACTION RATES
This page describes and explains the way that changing the concentration of a solution affects the rate of a reaction. Be aware that this is an introductory page only. If you are interested in orders of reaction, you will find separate pages dealing with these. You can access these via the rates of reaction menu (link at the bottom of the page).
The factsWhat happens? For many reactions involving liquids or gases, increasing the concentration of the reactants increases the rate of reaction. In a few cases, increasing the concentration of one of the reactants may have little noticeable effect of the rate. These cases are discussed and explained further down this page. Don't assume that if you double the concentration of one of the reactants that you will double the rate of the reaction. It may happen like that, but the relationship may well be more complicated. | |
Note: The mathematical relationship between concentration and rate of reaction is dealt with on the page about orders of reaction. If you are interested, you can use this link or read about it later via the rate of reaction menu (link at the bottom of the page). | |
| Some examples The examples on this page all involve solutions. Changing the concentration of a gas is achieved by changing its pressure. This is covered on a separate page. | |
Note: If you want to explore the effect of changing pressureon the rate of a reaction, you could use this link. Alternatively, use the link to the rates of reaction menu at the bottom of this page. | |
| Zinc and hydrochloric acid In the lab, zinc granules react fairly slowly with dilute hydrochloric acid, but much faster if the acid is concentrated.   The catalytic decomposition of hydrogen peroxide Solid manganese(IV) oxide is often used as a catalyst in this reaction. Oxygen is given off much faster if the hydrogen peroxide is concentrated than if it is dilute.  The reaction between sodium thiosulphate solution and hydrochloric acid This is a reaction which is often used to explore the relationship between concentration and rate of reaction in introductory courses (like GCSE). When a dilute acid is added to sodium thiosulphate solution, a pale yellow precipitate of sulphur is formed.  As the sodium thiosulphate solution is diluted more and more, the precipitate takes longer and longer to form. | |
http://www.chemguide.co.uk/physical/basicrates/concentration.html
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