Answer:
Basicity is measured on a scale called the pH scale. On this scale, a pH value of 7 is neutral, and a pH value of more than 7 to 14 shows increasing basicity.
pH value of 7 is weak base and value of 14 means strong base.
In an endothermic reaction, the heat in going in. it absorbs energy from its surroundings.
hope this helps!
Answer:
its atomic number
Explanation:
the mass number/atomic mass is how many protons and neutrons are combined in an element. But, the atomic number is just protons.
Answer:
-6.4x10⁻¹⁹ C
Explanation:
The elementary charge of one electron is -1.60x10⁻¹⁹C, so each electron has its charge, and a sample with more than one electrons will have a multiple of its charge, which is proportional to the number of electrons. So, if the oil droplet had 4 electrons, thus the charge will be four times the elementary charge:
4*(-1.60x10⁻¹⁹) C = -6.4x10⁻¹⁹ C
Answer:
1. 1.25 mol ants x 6.02*10^23 ants/1 mol ants = 7.53*10^23 ants
2. 4.92*10^26 pencils x 1 mol pencils/6.02*10^23 pencils = 817 mol pencils
3. 0.26 mol molecules x 6.02*10^23 molecules/1 mol molecules = 1.6*10^23 molecules
4. 3.46*10^19 molecules x 1 mol molecules/6.02*10^23 molecules = 5.75*10^-5 mol molecules
5. 5.3*10^20 atoms x 1 mol atoms/6.02*10^23 atoms = 8.8 mol atoms
6. 0.11 mol atoms x 6.02*10^23 atoms/1 mol atoms = 6.6*10^22 atoms
I would suggest looking into "dimensional analysis" for help with this type of material. Dimensional analysis will stick with you all throughout chemistry, so picking it up will be extremely beneficial.