An empirical formula shows the actual number of atoms of each element in a compound.

How many grams of ice at -12.1 ∘C can be completely converted to liquid at 15.2 ∘C if the available heat for this process is 4.4

ra1l [238]

Answer:

The mass of ice is 1,06 kg

Explanation:

Formula for calorimetry: Q = m . C . ΔT

Formula for phase transition, with latent heat: Q = L . m

m . C . ΔT + L . m + m . C . ΔT = 4490 kJ

m . 2,01 J/g°C (0° - (-12,1°C) + 334 J/g . m + m . 4,186 J/g°C . (15,2°C - 0°C)

Our unknown value is mass

You should look for latent heat of Ice and of course, specific heat of water.

Those are constant and they are known.

As the units are in J, and the heat for the process is in Kj we have to convert the final number into J

4490kJ . 1000 = 449000 J

m. 2,01 J/g°C (0°-(-12,1°C) + 334 J/g .m +m .4,186 J/g°C .(15,2°C - 0°C) = 449000 J

m. 24,321 J/g + 334 J/g .m + 63,62 J/g . m = 449000 J

421,94 J/g . m = 449000 J

m = 449000 J /421,94 g/J = 1064,1 g ---->1,06 kg

8 0

3 years ago

How many atoms in total are there in 7.35 mol of magnesium oxide (MgO) molecules?

andreev551 [17]

Answer:

4.42 x 10^24

Explanation:

3 0

3 years ago

Can you answer this for me

MrRissso [65]

Answer:

Algebra is an area in mathematics that uses variables, in the forms of letters and symbols, to act as numbers or quantities in equations and formulas. Geometry is an area in mathematics that studies points, lines, varied-dimensional objects and shapes, surfaces, and solids.

Explanation:

It is your own opinion on which is more difficult. In my opinion, Geometry is more difficult.

7 0

3 years ago

Read 2 more answers

Frank has a sample of steel that weighs 80 grams. If the density of his sample of steel is 8 g/cm3 ,what is the samples volume?

kirill115 [55]

Answer: 10 cm3

Explanation:

Mass of sample of steel (m) = 80 grams

density of sample of steel (p) = 8 g/cm3 samples volume (v) = ?

Since density is obtained by dividing mass by volume, the density of the steel sample is expressed as:

density = mass / volume

p = m / v

make v the subject formula

v = m / p

v = 80 grams / 8 g/cm3

v = 10 cm3

Thus, the samples volume is 10 cm3

4 0

3 years ago

The teacher shows students a pictorial model of an atom. Which element is

frutty [35]

Answer:

C. Fluorine because the model has 9 protons which is represented by the atomic number

Explanation:

We usually identify an element by the number of protons in them. The number of protons is the atomic number of an atom.

Every atom has a specific number of protons in them.
This number of protons is the atomic number.
According to the periodic law, atoms are arranged on the periodic table based on their atomic number.
The given fluorine atom has 9 protons which represents the atomic number of the atom.
This way, the given number clearly shows the right model for identifying the chemical specie.

4 0

3 years ago