Answer:
Only 3 is correct.
Explanation:
The crystal of a metal or an ionic compound is called a cell, and there are 7 types of unit cells: cubic, tetragonal, orthorhombic, monoclinic, hexagonal, rhombohedral, and triclinic.
In a face-centered cubic cell (FCC) all angles are 90º and all lengths are equal. Each cubic cell has 8 atoms in each corner of the cube, and that atom is shared with 8 neighboring cells. So for a metal crystal, the atom is located at each of the eight lattice points, where it is shared equally between eight unit cells.
Answer:

Explanation:
Hello,
Based on the given chemical reaction, as 31.2 mL of hydrogen are yielded, one computes its moles via the ideal gas equation under the stated conditions as shown below:

Now, since the relationship between hydrogen and magnesium is 1 to 1, one computes its milligrams by following the shown below proportional factor development:

Best regards.
Answer:
c. Bomb calorimetry
Explanation:
The hydrocarbons are combustibles, it means that they can react in a combustion reaction to release energy. To measure this amount of energy, it's necessary equipment that the reaction can be placed in a controlled way. The bomb calorimeter is this equipment, which is an adiabatic vessel, with water. The heat is calculated based on the increase in the water temperature.
The coffee-cup calorimetry is used to measure the heat of a dissolution reaction and the bomb manometry is used to measure the pressure.
Answer:
This question is incomplete
Explanation:
This question is incomplete as the volume of the base that was used during the titration was not provided. However, the completed question is in the attachment below.
The formula to be used here is CₐVₐ/CbVb = nₐ/nb
where Cₐ is the concentration of the acid = unknown
Vₐ is the volume of the acid used = 25 cm³ (as seen in the question)
Cb is the concentration of the base = 0.105 mol/dm³ (as seen in the question)
Vb is the volume of the base = 22.13 cm³ (22.1 + 22.15 + 22.15/3)
nₐ is the number of moles of acid = 1 (from the chemical equation)
nb is the number of moles of base = 2 (from the chemical equation)
Note that the Vb was based on the concordant results (values within the range of 0.1 cm³ of each other on the table) of the student
Cₐ x 25/0.105 x 22.13 = 1/2
Cₐ x 25 x 2 = 0.105 x 22.13 x 1
Cₐ x 50 = 0.105 x 22.13
Cₐ = 0.105 x 22.13/50
Cₐ = 0.047 mol/dm³
The concentration of the sulfuric acid is 0.047 mol/dm³
Answer:

Explanation:
We are asked to find the specific heat capacity of a sample of lead. The formula for calculating the specific heat capacity is:

The heat absorbed (Q) is 237 Joules. The mass of the lead sample (m) is 22.7 grams. The change in temperature (ΔT) is the difference between the final temperature and the initial temperature. The temperature increases <em>from</em> 29.8 °C <em>to </em>95.6 °C.
- ΔT = final temperature -inital temperature
- ΔT= 95.6 °C - 29.8 °C = 65.8 °C
Now we know all three variables and can substitute them into the formula.
- Q= 237 J
- m= 22.7 g
- ΔT = 65.8 °C

Solve the denominator.
- 22.7 g * 65.8 °C = 1493.66 g °C

Divide.

The original values of heat, temperature, and mass all have 3 significant figures, so our answer must have the same. For the number we found that is the thousandth place. The 6 in the ten-thousandth place tells us to round the 8 up to a 9.

The specific heat capacity of lead is approximately <u>0.159 Joules per gram degree Celsius.</u>