A theory does not change into a scientific law with the accumulation of new or better evidence. A theory will always remain a theory
Here are the answers in order:
1. During a physical change the substance changes physically.
2. The law of conservation of mass is a law stating the conservation of mass cannot be higher than 46mg or lower than 32mg.
3. A hypothesis is a guess that you make before completing a science experiment, it can be considered a law because it is important to know why you are making the guess.
4. During a chemical change the mass is changing colors. This is a representation of a chemical change.
5. Oil is a non-renewable resource, so it cannot demonstrate the conservation of mass.
6. When the color of the substance has changed or when it explodes.
7. Reactants are the objects that react when in a chemical change.
8. If you follow the rule of not going higher than 46mg and not lower than 32mg then it will automatically follow this law.
Chemical Reactions Part One Video:
1. mass
2. erupt-ant
3. reactant
4. object
5. mixtures
6. molecules
7. color changed
Questions again:
1. A chemical reaction
2. A physical change
3. Because if it is no higher than 46mg and no lower than 32mg then it will follow on it's own.
Answer:
a) octahedral electron domain geometry
b)square planar molecular geometry
c) a bond angle of 90°
Explanation:
According to the Valence Shell Electron Pair repulsion Theory, the shape of a molecule is dependent on the number of electron pairs on the valence shell of the central atom in the molecule. These electron pairs orient themselves as far apart in space as possible to minimize electron pair repulsion.
Electron pairs may be lone pairs or bond pairs. Lone pairs of electrons cause more repulsion than bond pairs. These lone pairs often cause the molecular geometry to depart from what is predicted on the basis of the electron domain geometry due to greater repulsion of lone pairs.
When a molecule has six electron domains consisting of four bond pairs and two lone pairs, the bonding pairs arrange themselves at the corners of a square at a bond angle of 90° with the lone pairs found above and below the plane of the bonding groups leading to a square planar molecular geometry
Semiconductors are made of the metalloids silicon and germanium