In this exercise, you will calculate molar value of ΔH (in kJ/mol) for dissolving NH4H2PO4 in Part D of the Calorimetry lab. (a) What temperature change did you find for dissolving NH4H2PO4 in Part D of the experiment? (Include the + or - sign in your answer.) WebAssign will check your answer for the correct number of significant figures. -.74 Correct: Your answer is correct. °C (b) What mass of water did you find in Part D of the experiment? WebAssign will check your answer for the correct number of significant figures. 98.760 Correct: Your answer is correct. g (c) What mass of NH4H2PO4 did you dissolve in Part D of the experiment? WebAssign will check your answer for the correct number of significant figures. 8.646 Correct: Your answer is correct. g (d) Calculate ΔH in kilojoules for your reaction in Part D. (Enter your answer to three significant figures.) WebAssign will check your answer for the correct number of significant figures..128 Incorrect: Your answer is incorrect. kJ (e) Calculate the molar value of ΔH (in kJ/mol) for t

personal, she chose to do it.

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.

water at room temperature is flowing through a pipe with pressure taps located 10 ft apart along one section of the pipe, which are connected to a mercury (s=13.6) manometer.