Grace measures 20mL of water in a graduated cylinder. she puts a piece of rock in the graduated cylinder and measures the new volume of water to be 32mL. what is the volume of
the rock?

Explanation:

Grace found the volume of the rock using water displacement.

To calculate the volume, we must subtract the initial volume from the final volume.

The initial or original volume is 20 milliliters.

The final or new volume, after the rock is added to the water, is 32 milliliters.

Substitute the values into the formula and subtract.

The volume of the rock is 12 milliliters.

3

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.