Answer:
Physical change
Explanation:
Chemical change is defined as the process in which new substance with different properties is formed from old substance and the process is irreversible while physical change is a reversible process and changes only physical properties of a substance.
<em>The given experiment is an example of physical change because it is just the physical act of dissolving. The metal disk is dissolving in sodium acetate and the process is exothermic and the process is reversible as well.</em>
Hence, the correct answer is "physical change".
<span>A. It increases the number of collisions between molecules.
I hope this helps :)</span>
Answer:
Au
Explanation:
For the density of a face-centered cubic:
where
= molar mass of the compound
avogadro's constant
the volume of a unit cell
Given that:
Density 
= 19.30 g/cm³
a = 0.408 nm
a = 
a = 
∴
Thus, the molar mass of 197.37 g/mol element is Gold (Au).
Answer:
the volume of CHCI3 = 7.87 ml
the volume of CHBr3 = 12.13 ml
Explanation:
From the given information:
We all know that 1 g/cm^3 = 1 g/ml
The density of boron = 2.34 g/ml
The Volume of the liquid mixture = 20 ml
Recall that:
Density = mass/volume
Mass = Density × Volume
Mass = 2.34 g/ml × 20 ml
Mass = 46.8 g
Suppose the volume of CHCI3 be Y and the Volume of CHBr3 be 20 - Y
Then :
Y (1.492) + 20-Y(2.890) = 46.8
1.492Y + 57.8 - 2.890Y = 46.8
- 1.398 Y = -11
Y = -11/ - 1.398
Y = 7.87 ml
Therefore, the volume of CHCI3 7.87 ml
the volume of CHBr3 = 20 - Y
= 20 - 7.87
= 12.13 ml
