Science Christmas Exams Flashcards
Atom
Atoms consist of a nucleus made of protons and neutrons orbited by electrons. Atoms are the basic units of matter and the defining structure of elements.
atomic mass
Number of protons and neutrons
atomic number
the number of protons in an atom
Element
A chemical made up of only one kind of atom is called an element
electron configuration
Electronic configuration is the arrangement of the electron in the atom. Electrons are arranged in Energy levels or shells and sub-shells around the nucleus of an atom.
Main energy levels: K(1), L(2), M(3), N(4)
Sub energy levels: s2, p6, d10, f14 (always put 3d10 after 4s6)
periodic table
There are 18 groups(columns) and 7 periods(rows) in a periodic table. Metals are in the groups: 1, 2, 13. Non metals are in the groups 13-17.
Isotope
Isotopes are atoms of the same element (X) with different numbers of neutrons in their nuclei
ions
An ion is an atom, or group of atoms, that has a net positive or negative charge.
Cation: an ion with a positive charge
Anion: an ion with a negative charge
Electronegativity
Electronegativity is a chemical property that says how well an atom can attract electrons towards itself.
Strong and weak chemical bonds:
Bonds are stronger between atoms are stronger than bonds with molecules.
Ionic compounds:
The ionic bond is between metals and non-metals. The metals lose an electron while the nonmetals gain an electron. The metals lose electrons from 1-3 and the nonmetals gain electrons from 1-3.
Covalent compounds:
Covalent bonds share electrons between nonmetals.
Metallic bonds
Metallic bonds are between atoms of the same metals like N2 for example. Metallic bonds can conduct electricity because they have a sea of free electrons.
Hydrogen bonds:
a weak chemical bond between an electronegative atom, such as fluorine, oxygen, or nitrogen, and a hydrogen atom bound to another electronegative atom.
Balancing equations:
keep mass of products and reactants the same by adjusting coefficients as necessary
Factors affecting rates of Chemical Reactions:
concentration, temperature, catalysts
Polar molecules:
Molecules that have unequal distribution of charges. When one atom has a higher electronegative charge than the other and attracts the shared pair of electrons. For example like H2O.
Non polar molecules:
A nonpolar molecule has no separation of charge, so no positive or negative poles are formed. In other words, the electrical charges of nonpolar molecules are evenly distributed across the molecule.
Solubility
Solubility is the ability to dissolve into (become a part of) another substance.
Detergents
Soaps for example have a polar and a non-polar side. The polar side attracts water and other polar molecules and the non-polar side attracts non-polar molecules like oil.
Water:
H2O
water cycle
The water cycle describes how water evaporates from the surface of the earth, rises into the atmosphere, cools and condenses into rain or snow in clouds, and falls again to the surface as precipitation.
Nutrients
Nutrients are compounds in foods essential to life and health, providing us with energy.
Carbohydrates
Carbohydrates are your body’s main source of energy. When you eat carbs, your body breaks them down into simple sugars, which are absorbed into the bloodstream .
Proteins (essential and non-essential amino acids)
Protein makes up the building blocks of organs, muscles, skin and hormones. Your body needs protein to maintain and repair tissues. (Proteins are like meat, fish, beans, eggs and almonds.) Proteins are made of monomer amino acids (acidic group and carboxyl group). Multiple amino acids in a polymer make a protein.
Denaturation
Denaturation is process which breaks down the molecular structure of protein. This process breaks down the weak bonds in the protein to create a more irregularly structured proteins.
Fat (Saturated, Unsaturated and trans fats)
Fat is a form of fuel used by your body. Fats is essential for cell growth and recovery.
Saturated Fats
These fats are found in meat and other animal products, such as butter and cheese. Saturated fats can increase the LDL level in your body, which can cause heart diseases.
Unsaturated Fats
These are found in plant foods and fish. These facts are good for heart health.