Keyterms Chemistry Flashcards
What’s an Ionic Compound?
- A substance formed with cations and anions. Generally, it is formed with
a (metal) and a (nonmetal) with the metal being a cation and the nonmetal being an anion.
What’s an Ion?
A charged atom
What’s a Cation?
A positively charged atom (lost electrons)
What’s an Anion?
- A negatively charged atom (gained electrons)
What’s a Valence Electron?
- Electrons on the last layer of an atom
What’s a Binary ionic compound?
- An ionic compound composed of two ions
What’s a Polyatomic ion?
- A bond formed between two or more ions
What’s a Ternary compound ?
A compound formed between three ions
What’s a Molecular compound(covalent compounds)?
- a group of atoms bonded to form a molecule
A molecular compound is made when two or more nonmetals share electrons.
(Examples are water (H₂O) and carbon dioxide (CO₂). These compounds usually have low melting points and don’t conduct electricity.)
What’s a Molecule?
- Two or more atoms that form a covalent bond
What’s a Binary molecular compound?
(- A Molecular compound formed by two types of atoms)
A binary molecular compound is a compound made of two different nonmetals.
Carbon dioxide (CO₂): Made of carbon and oxygen.
What’s a Reactant?
- Substances involved in a chemical reaction
A reactant is a substance that starts a chemical reaction. It changes to form products. For example, in the reaction of water, hydrogen and oxygen are the reactants.
What’s a product?
- Substances created as a result of a chemical reaction
What’s a chemical equation?
A chemical equation shows what happens in a chemical reaction. It uses symbols to show the starting materials (reactants) and the new substances (products).
For example:
2H₂ + O₂ → 2H₂O
What’s a Chemical equation?
A chemical equation is a way of showing a chemical reaction using symbols and formulas. It shows the reactants (starting materials) and products (what’s made) in the reaction.
For example:
H₂ + O₂ → H₂O
What’s a Coefficient?
A coefficient is a number placed in front of a chemical formula in a chemical equation to show how many molecules or atoms of a substance are involved in the reaction.
For example, in the equation 2H₂ + O₂ → 2H₂O
the 2 in front of H₂ and H₂O indicates there are two molecules of hydrogen (H₂) and two molecules of water (H₂O) involved.
What’s a word equation?
the name of each reactant on one side and the product on the other Hydrogen + oxygen -> water
What’s a Skeletal equation?
- Instead of names chemical formulas are used H2+O2 -> H2O
What’s Balanced chemical equation?
- Coefficients are added to ensure that the mass is the same 2H2+O2 -> 2H2O
What’s the states of substances?
Solid(s), Liquid(l), Gas(g), Aqueous(dissolved in a liquid) solution(aq)
What’s Precipitate?
A precipitate is a solid that forms in a liquid when two liquids react.
It’s like when something “falls out” of the liquid.
For example, mixing two clear liquids can make a solid appear at the bottom of the container.
(- a substance that forms as a result of a chemical reaction)
What’s a Synthesis reaction?
A synthesis reaction is when two or more simple reactants combine to form a more complex substance. The general formula is:
A + B → AB
For example, when hydrogen gas (H₂) reacts with oxygen gas (O₂), they form water (H₂O):
2H₂ + O₂ → 2H₂O
Here, two simple molecules (hydrogen and oxygen) combine to make a more complex molecule (water).
What’s a Decomposition reaction?
A decomposition reaction is when a single compound breaks down into two or more simpler reactants.
The general formula is: AB → A + B
For example, when calcium carbonate (CaCO₃) is heated, it breaks down into calcium oxide (CaO) and carbon dioxide (CO₂):
CaCO₃ → CaO + CO₂
In this case, one compound (calcium carbonate) breaks down into two simpler substances (calcium oxide and carbon dioxide).
What’s a Single displacement reaction?
A single displacement reaction is when one element replaces another in a compound.
The general formula is:
A + BC → AC + B
For example, when zinc (Zn) reacts with hydrochloric acid (HCl), zinc replaces hydrogen to form zinc chloride (ZnCl₂) and hydrogen gas (H₂):
Zn + 2HCl → ZnCl₂ + H₂
In this reaction, zinc displaces hydrogen from hydrochloric acid.
What’s an Activity series?
An activity series is a list that ranks metals by how reactive they are. The most reactive metals are at the top, and the least reactive are at the bottom.
For example, a metal higher in the series can replace a metal lower in the series in a reaction. So, zinc can replace copper in a compound, but copper can’t replace zinc.
- Most reactive metals (like sodium) are at the top.
- Least reactive metals (like gold) are at the bottom.
What’s a Double displacement reaction?
A double displacement reaction is when two compounds react, and the positive and negative ions of each compound switch places to form two new compounds. The general formula is:
AB + CD → AD + CB
For example, when silver nitrate (AgNO₃) reacts with sodium chloride (NaCl), silver chloride (AgCl) forms as a precipitate, and sodium nitrate (NaNO₃) remains in solution:
AgNO₃ + NaCl → AgCl (s) + NaNO₃
In this reaction, the silver (Ag⁺) switches with the sodium (Na⁺), and the chloride (Cl⁻) switches with the nitrate (NO₃⁻).
What’s a Catalyst?
A catalyst is a substance that speeds up a chemical reaction without being used up. It helps the reaction happen faster but remains unchanged after the reaction.
Example:
In the breakdown of hydrogen peroxide (H₂O₂), the enzyme catalase speeds up the reaction, turning hydrogen peroxide into water (H₂O) and oxygen (O₂), but the catalase isn’t used up:
2H₂O₂ → 2H₂O + O₂
So, catalase helps the reaction go faster but stays the same.
What’s Leaching?
Leaching is when a liquid is used to dissolve and remove a substance from a solid.
For example, in mining, chemicals like cyanide are used to dissolve gold from rocks. In soil, rain can wash away nutrients, which is also a type of leaching.
What’s a halo-gen?
A halogen is an element from group 17 of the periodic table. The halogens include:
_________________highest
Fluorine (F)
Chlorine (Cl)
Bromine (Br)
Iodine (I)
Astatine (At)
_________________lowest
What’s acid?
An acid is a substance that releases hydrogen ions (H⁺) when dissolved in water.
Acids are usually sour and can turn blue litmus paper red.
- Lemon juice (citric acid)
- Vinegar (acetic acid)
- Hydrochloric acid (found in stomach acid)
In simple terms, acids are chemicals that can “donate” hydrogen ions.
What’s Binary acid?
A binary acids is an acid made of two elements: hydrogen and one nonmetal (like chlorine or sulfur).
Examples:
-Hydrochloric acid (HCl)– hydrogen and chlorine.
- Hydro sulfuric acid (H₂S)– hydrogen and sulfur.
These acids are named with “hydro-“ and the nonmetal name ending in “-ic.”
What is Oxoacid?
An oxoacid is an acid that contains hydrogen, oxygen, and another element (like sulfur or nitrogen).
Examples:
- Sulfuric acid (H₂SO₄)– hydrogen, oxygen, and sulfur.
- Nitric acid (HNO₃)– hydrogen, oxygen, and nitrogen.
In oxoacids, the hydrogen is bonded to oxygen, which is then bonded to another element.
What’s the Ph scale?
The pH scale measures how acidic or basic (alkaline) a substance is. It ranges from 0 to 14:
- pH 7 is neutral (neither acidic nor basic), like pure water.
- pH less than 7 indicates an acid, with lower numbers being more acidic (e.g., lemon juice, vinegar).
- pH greater than 7 indicates a base (or alkaline), with higher numbers being more basic (e.g., soap, baking soda).
The scale is logarithmic, meaning each step on the scale represents a tenfold difference in acidity or alkalinity.
What’s pH indicator?
A pH indicator is a substance that changes color to show whether a solution is acidic, neutral, or basic.
Examples:
- Litmus paper: Red in acids, blue in bases.
- Phenolphthalein: Colourless in acids, pink in bases.
- Universal indicator: Shows a range of colors from red (acidic) to purple (basic).
Indicators are used to test the pH of a solution.
What’s Neutralization?
Neutralization is a reaction between an acid and a base that produces water and a salt, making the solution neutral.
Example:
When hydrochloric acid (HCl) reacts with sodium hydroxide (NaOH), it forms water (H₂O) and salt (NaCl):
HCl + NaOH → H₂O + NaCl
In simple terms, neutralization happens when an acid and a base cancel each other out.
What’s Liming?
Here’s a simplified version of your points:
- Liming: The process of adding calcium carbonate to soil to neutralize acidity.
- Example of Neutralization:
HCl + NaOH → H₂O + NaCl
This shows how an acid (HCl) reacts with a base (NaOH) to form water and salt. - Double Displacement Reaction: Neutralization is also a type of double displacement reaction, where two compounds exchange ions to form new compounds.
- Examples of Acids in Nature**:
- Acid rain: Rain with harmful acidic substances.
- Acid spills: Accidental release of acidic chemicals.
- Acid cleanup: The process of neutralizing or cleaning up acid spills.
This covers the process and examples clearly and simply.
