It is a physical change when cream mixes with
coffee, it changes the color of the coffee. When you add more or less cream there
is a color change depending on the consistency of cream. The
properties are not changes and a no new compound is formed as in chemical
change with a reaction of two compounds, a new compound is formed with
different properties. So it is a physical change.
1. O2 is not a compound because it only contains one or more type of the same element atom.
2. O2 is a molecule because a molecule is one or more of the same element atom.
3. The law of conversion is that the mass of the system will stay the same when transfer takes place. Like if you had an equation O+H2—> H2O the mass will remain the same.
4. It will be equal to 10 because of law of conservation of matter.
5. One observation can be that the compound, reaction you’re observing, has change states.
Answer: The empirical formula is 
.
Explanation:
Mass of C = 1.71 g
Mass of H = 0.287 g
Step 1 : convert given masses into moles.
Moles of C = 
Moles of H = 
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For C =
For H =
The ratio of C: H = 1: 2
Hence the empirical formula is .
Answer:
c. can have a large cumulative effect
Explanation:
Noncovalent interactions between molecules are weaker than covalent interactions. Noncovalent interactions between molecules are of various types which include van der Waals forces, hydrogen bonding, and electrostatic interactions or ionic bonding.
van der Waals forces are weak interactions found in all molecules. They include dipole-dipole interactions - formed due to the differences in the electronegativity of atoms - and the London dispersion forces.
Hydrogen Bonds results when electrons are shared between hydrogen and a strongly electronegative atoms like fluorine, nitrogen, oxygen. The hydrogen acquires a partial positive charge while the electronegative atom acquires a partial negative. This results in attraction between hydrogen and neighboring electronegative molecules.
Ionic bonds result due to the attraction between groups with opposite electrical charges, for example in common salt between sodium and chloride ions.
Even though these noncovalent interactions are weak, cumulatively, they exert strong effect. For example, the high boiling point of water and the crystal structure of ice are due to hydrogen bonding.
Answer:
Explanation:
The number of valence electrons tells us the group number of the neutral atom.
The atom has 4 valence electrons.
The atom is in group 4.
