<span>Dmitri Mendeleev's Periodic Law states that chemical and physical properties repeat themselves in groups of 8.</span>
Endothermic reactions, on the other hand, absorb heat and/or light from their surroundings. For example, decomposition reactions are usually endothermic. In endothermic reactions, the products have more enthalpy than the reactants. Thus, an endothermic reaction is said to have a positive<span> enthalpy of reaction. This means that the energy required to break the bonds in the reactants is more than the energy released when new bonds form in the products; in other words, the reaction requires energy to proceed</span>
That's a lot of conversions...
107*7 = 749km in one week
749/1.6 = 468.125 miles
468.125/39 = <span>12.0032051282 gallons of fuel needed
</span>1 gallon = 4.54609 litres
1.1(Cost per litre)*4.54609(Number of litres per gallon)*12.0032051282(Number of gallons needed) = <span>60.0244158814 euros cost per week
</span>60.0244158814 * 1.26 = <span>75.6307640105 dollar cost per week
</span>$75.63
Answer:
Below in Bold
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♨ The word ' acid ' is derived from the Latin word ' acidus ' which means sour. An acid is defined as the substance which gives hydrogen ions or protons ( H+ ) when dissolved in water. For example :
- Hydrochloric acid
- Sulphuric acid
- Nitric acid
- Carbonic acid
- Acetic acid
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☃ Physical properties :
- Acids have a sour taste. But some acids like steric acid, boric acid , salisylic acid do not have a sour taste. Laboratory acids are more corrosive , so they are dangerous to taste.
- Acid turn blue colour of litmus paper into red and light yellow methyl orange into red. They make phenolphthalein colourless.
☂ Chemical properties :
- Acids have a high dissolving power and dissolve many substances. Some metals like zinc and magnesium react with acids like dilute sulphuric acid and dilute hydrochloric acid to produce salt and hydrogen gas.
- Acid react with base to give salt and water.
- Acid gives H+ ions when dissolved in water.
- Acid react with metallic carbonates to produce carbon dioxide.
☼ Hope I helped! ♡
Have a wonderful day / night ! ツ
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