chemistry
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27 questions
| 🇬🇧 | 🇬🇧 |
| What are cations | Positive ions normally metals |
| What are anions | Negative ions normally non metals |
| How do you test for cations? | A nichrome wire is dipped into hydrochloric acid HCL. Then dip it into the salt or compound. Hold it above the blue flame on the bunsen burner to get the colour |
| What colour does the cation Ca make | Orange or red |
| How do i Test for cations using Sodium Hydroxide: | Place 1cm3 of element salt into a test tube Add 1cm3 of Sodium Hydroxide into the tube and record results |
| How many elements are tested for cations using hydrochloric acid | Li, Na, K, Cu , ca |
| How many elements are used for cations using sodium hydroxide | Cu, Fe2, Fe3, NH4 |
| What is made when sodium hydroxide is used for Cu | Blue precipitate |
| What is made when sodium hydroxide is used for Fe3 | Orange red brown |
| How do i test for halides or anions | If it’s in a salt form you must add nitric acid to make it acidic and get rid of anything that might interfere with the tests. Once it’s a solution, in a test tube take sample x and add silver nitrate solution into it. Observe the colour. |
| What three halides are there | Bromine chlorine iodine |
| How do i test for sulfafte ions or anions | If the substance is not as a solution, then add nitric acid to make it into a solution. Place the solution into a test tube and add some barium chloride solution into it. If sulfate ions are present, then a white precipitate of Barium Sulfate will form. |
| How do i test for carbonate ions | • Take the substance as a solid or a solution • Add hydrochloric acid to the solution • If the limewater solution goes cloudy then carbon dioxide is present. • This means that the substance contains Carbonate. |
| How do i test for oxygen | Take a glowing splint and place into the test tube. If it RELIGHTS, then it is present. |
| How do i test for hydrogen | Take a lit splint and place it at the mouth of the test tube. If it EXPLODES WITH A SQUEAKY POP, then it is present. |
| How do i test for co2 | The carbon dioxide gas is bubbled through calcium hydroxide solution or limewater. It TURNS CLOUDY AND THERE IS A WHITE PRECIPITATE of (calcium carbonate) AT THE BOTTOM then it is present. |
| How do i test for chlorine | Take a piece of damp litmus paper and hold it over the mouth of the test tube. If it bleaches the paper and turns it white, then it is present. h |
| How do i test for ammonia | Take a piece of damp universal paper or a red litmus paper and hold it over the mouth of the test tube. If it TURNS THE DAMP PAPER BLUE, then it is present. |