The fluorocarbon compound c2cl3f3 has a normal boiling pointof
47.6 degrees c. the specific heats of c2cl3f3(l) andc2cl3f3(g) are
0.91j/g-k and 0.67j/g-k, respectively. theheat of vaporization for
the compound is 27.49kj/mol. claculate the heat required to convert
25.0g of c2cl3f3 from aliquid at 5.00degrees c to a gas at
82.00degree c.

5.21 kJ

Explanation:

The transformation happens in steps. First, the liquid solution gains heat (Q1) and has its temperature elevated from 5.00°C to 47.6°C. Then, it vaporizes at a constant temperature, with the heat of vaporization (Q2). After that, the substance gains heat (Q3) and the temperature increases to 82.00°C.

The heat of the transformation with the change in temperature can be calculated by:

Q = m*c*ΔT, where m is the mass, c is the specific heat and ΔT the temperature variation.

The heat of the phase change is the heat of vaporization multiplied by the number of moles of the substance.

The total heat required is the sum of the heats of the steps. The molar mass of C2Cl3F3 is 187.4 g/mol. The number of moles is the mass divided by the molar mass:

n = 25/187.4 = 0.1334 mol

So,

Q1 = 25.0 g * 0.91 J/g.K * (47.6 - 5.00)K = 969.15 J

Q2 = 0.1334 mol * 27.49 kJ/mol = 3.6672 kJ = 3667.2 J

Q3 = 25.0 g * 0.67 J/g.K * (82.00 - 47.6)K = 576.2 J

Q = 969.15 + 3667.2 + 576.2

Q = 5212.55 J

Q = 5.21 kJ

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.

answer; talc and gypsum;