When the positives and negatives are in equal number, they neutralize each other. This makes them very reactive with anything they contact. They either have too many positive charges and are looking for negatives to get back into balance, or they have too many negative charges and are looking for positives to get back into balance. One last question: Why are strong acids and strong bases so nasty? It's because they are out of balance. If we add NaOH to water, it dissociates into Na + and OH -. The sodiums don't do anything important, but the hydroxyls make the solution more basic. Now let's look at lye, a strong base with the chemical formula NaOH (sodium hydroxide). The H + ions combine with water molecules to form H 3O + so the solution becomes acidic. When dissolved in water, it becomes CH 3COO - and H +. Vinegar, a weak acid, has a chemical formula of CH 3COOH. When we dissolve bases in water, we create an excess of hydroxyls. When we dissolve acids in water, we create an excess of hydroniums. Watch out for that, and ask for clarification! Note: Sometimes people write H + as a shorthand for H 3O + and that can cause confusion, because sometimes when people write H + they really do mean only H + and not H 3O +. pH actually stands for the "potential (or power) of hydrogen." If there are more negatively charged hydroxyls than positively charged hydroniums, then the substance becomes basic. If there are more positively charged hydroniums than negatively charged hydroxyls, then the substance is acidic. So how does something become acidic or basic? That happens when the hydroniums and the hydroxyls are out of balance. Pure water is neither acidic or basic it is neutral. However, in water, there is a balance between hydroniums and hydroxyls so they cancel each others' charges. H 3O + is called a hydronium ion, and it makes things acidic. OH - is called a hydroxyl ion and it makes things basic. The alkaline solutions it forms when dissolved in water neutralize acids in various commercial processes. Add 4 to 5 drops of phenolphthalein indicator solution to. Add distilled water from the squeeze-bottle so that the total volume in the flask is between 20 mL and 30 mL. Empty the cylinder totally, by waiting until the last drops fall. One water molecule gains a hydrogen and therefore takes on a positive charge, while the other water molecule loses a hydrogen atom and therefore becomes negatively charged. It is highly corrosive to animal and vegetable tissue. Transfer the 5.0-mL sample of citric acid solution for trial 1 from the cylinder into a 125-mL Erlenmeyer flask. We begin with two water molecules, and move some hydrogen atoms around. What makes a substance acidic or basic? The following equation is a good place to start: 2 H 2O ⇌ 1 H 3O + + 1 OH. However, mild acids and bases are common and relatively harmless to us. Strong acids are corrosive and strong bases are caustic both can cause severe skin damage that feels like a burn. The terms acid and base describe chemical characteristics of many substances that we use daily.
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