Science CHem Notes Flashcards
(42 cards)
What is Evolution?
Evolution is the change in traits in a population over multiple generations.
What is some evidence relating to evolution?
Fossils, DNA and Homologous structure
How do Fossils prove evolution?
The fossils lower and lower can be viewed as a more primitive version of fossils higher up on the rock layer which allows us to view the succession of evolution through the timeline of fossils.
How does homologous structures prove evolution?
homologous structures support the theory of evolution by demonstrating shared ancestry and the adaptive changes that occur over time. (physical features found in different organisms that share a common ancestor and illustrate descent from a common evolutionary origin.)
How do you interpret the ages of rock
you interpret the ages of rock by using Relative Dating and Radioactive decay.
How do you use Relative Dating to find the age of rocks?
By comparing rock layers geologists can find the age of rocks, but not to the exact age
How do you use Radioactive Decay to find the age of rock?
By measuring the quantity of unstable radioactive isotopes left in a rock and comparing it to the quantity of stable daughter products
What is the Conservation of Mass?
the total mass of a closed system remains constant over time. This means that mass cannot be created or destroyed, but it can change forms.
What is the difference of physical of chemical change?
Physical changes are changes that can be reversed while chemical changes are irreversiblePhysical changes are changes that can be reversed while chemical changes are irreversible.
What is an ionic compound or bond?
An ionic bond is when two oppositely charged ions attract to each other
What is a covalent compound/bond?
A covalent bond is a chemical bond that involves the sharing of electrons to form electron pairs between atoms
How do you name ionic compounds?
for ionic compounds the name is formed by listing the cation (positively charged ion) first, followed by the anion (negatively charged ion) with the suffix “-ide” if it is a nonmetal. If the anion is polyatomic, the name of the polyatomic ion is used without the “-ide” suffix. For example, sodium chloride (NaCl) is named by listing sodium (the cation) first and then chloride (the anion).
How do you name covalent compounds?
While for covalent compounds the name of the first element in the formula is written first, followed by the second element’s name with the suffix “-ide”. If there is more than one atom of the first element, numerical prefixes are used to indicate the number of atoms. For example, carbon tetrachloride (CCl4) is named by listing carbon first and then using the prefix “tetra-“ to indicate four chlorine atoms
What is an acid?
An acid is a substance that produces hydrogen (H+) ions when it is added to water.234 Acids have a pH less than ,7 and taste sour.
What is a base?
A base is a substance that can accept hydrogen ions (H+) or protons, have a ph higher 7 and are bitter
What is neutralisation?
A chemical reaction where an acid and a base react to form a salt and water, typically resulting in a neutral pH solution
What happens when you add an acid to a metal?
a chemical reaction occurs where the metal displaces hydrogen from the acid, producing hydrogen gas and a salt
What happens when you add a base to a metal?
When base reacts with the metal it form the metalic salt and displace hydrogen. Example - Zn + 2 NaOH →Na 2 ZnO 2 + H 2 gas
What happens when you add an acid to a carbonate?
a reaction occurs that produces a salt, water, and carbon dioxide gas
What happens when you add a base to a carbonate?
No chemical reaction occurs
What is a displacement reaction?
a chemical reaction in which one element replaces another element in a compound.
AB + CD -> AD + CB
What is a combination reaction?
a type of chemical reaction where two or more substances combine to form a single new substance without any separate byproducts.
A + B -> AB
What is a decomposition reaction?
A decomposition reaction is a type of chemical reaction in which a single compound breaks down into two or more simpler substances.
AB -> A + B
What is a combustion reaction?
a type of chemical reaction in which a substance, often a fuel, reacts with an oxidant, usually oxygen, to produce heat and light, typically in the form of a flame
