Plz will upvote
which is/are true?
[mark all correct answers]
a. chemists use the term mole as a counting unit to describe a set number of particles.
b. a mole indicates that there are 6.02 x 10 23 particles present.
c. amedeo avogadro determined the number of particles in a mole.
d. a mole of carbon has the same mass as a mole of hydrogen.
e. a mole of oxygen contains the same number of molecules as a mole of nitrogen.
f. the molar mass of sodium is 23.0 g/mol.

120,630,890

step-by-step explanation:

110+10=120,620+10=630,880+10=890

hloride, what is the mass of calcium in

explanation:

assuming that your periodic table has eighteen columns, you should highlight   the four elements in the third column from the left of the table.

neutral atoms of elements after calcium contain d electrons. the energy of d orbitals of a particular main shell lies between the energy of the s and p orbitals of the next main shell. for example, electrons in the have energy higher than those in the orbital while lower than those of the orbital.

by the aufbau principle, electrons fill orbitals one at a time, starting from those of the lowest energy. the orbital is therefore filled right after orbitals and before orbitals.  

potassium has electron configuration and calcium . the s orbital of a main shell holds a maximum of two electrons. the next element would thus have the electron configuration and satisfy the requirements.

a neutral atom of the element contains three electrons on top of the most recent noble gas element. it should thus be placed in the third column of the periodic table. both scandium and yttrium would satisfy the conditions. an aufbau diagram indicates that the 4f orbital is filled before the 5d. however, it appears that exceptions exists for both lanthanum and actinium. neutral atoms of the two d-block elements also demonstrate the and should be highlighted as well.

a pan containing water is placed in a positio n where it is exposed to a 10 mile per hour wind. the pan contains a uniform depth of 1.27 cm of water, is quite wide, and has a length of 2.44 m in the wind direction. the water in the pan is at a constant temperature of 15.5 °c.