Answer:
Explanation:
The relative atomic mass of an element is a weighted average of the masses of the atoms of the isotopes - because if there is much more of one isotope then that will influence the average mass much more than the less abundant isotope will.
An energy diagram of a chemical reactions illustrates the changes of energy as the chemical reactions advances.
At first, the energy in the diagram is the energy of the reactants.
As the reaction goes forward, the reactants start to react forming a transition compound, with a maximum energy level on the graph. This is the hill. So the hill represents the Activation Energy.
After that, the energy starts to decrease and at the end you have the energy of the products, which may be higher or lower than the initial energy of the reactants, depending upon whether the reaction is exothermic or endothermic.
For exothermic reactions the energy level of the products is lower than the energy level of the reactants, while for endothermic reactions the energy level of the products is higher than the energy level of the reactants.
Answer:
a. Volatile.
b. Air foil.
c. Sash.
d. Work surface.
Explanation:
In science, matter can be defined as anything that has mass and occupies space. Any physical object that is found on earth is typically composed of matter. Matter are known to be made up of atoms and as a result has the property of existing in states.
Generally, matter exists in three (3) distinct or classical phases and these are;
I. Solid.
II. Liquid.
III. Gas.
Matching the terms with their respective definition, we have;
a. Volatile: A characteristic that describes substances that evaporate readily, producing large amounts of vapors.
b. Air foil: the front vent of a fume hood, which helps maintain proper air circulation.
c. Sash: the glass panel in front of the fume hood that shields the user from fumes and other hazards.
d. Work surface: the horizontal, flat area of a fume hood upon which experiments are carried out.
1. An ion is a charged atom. A molecule is a neutrally-charged combination of atoms.
2. A molecule is a combination of atoms. It can consist of atoms from one or more elements. For example, an oxygen molecule comprises two oxygen atoms. A compound is a substance made up of a combination of atoms of different elements. For example, water is a compound of hydrogen and oxygen.
3. An electron dot diagram is a simple way of representing the bond and electronic structure of molecules. A formula is a written representation of the types and numbers of atoms in a molecule.
4. As above...a formula denotes which atoms are in a molecule and how many. For example, H2SO4 tells us there are two hydrogen atoms, one sulfur atom and four oxygen atoms in each molecule of sulfuric acid.
5. An ionic bond is a type of chemical bond that stems from electrostatic attraction between ions with opposite charges. A covalent bond is another type of chemical bond that involves sharing of electrons between atoms in order to achieve a stable electronic structure for the molecule as a whole.
