Answer:
When heat is added to a substance, the molecules and atoms vibrate faster. As atoms vibrate faster, the space between atoms increases. The motion and spacing of the particles determines the state of matter of the substance. The end result of increased molecular motion is that the object expands and takes up more space.
Explanation:
Answer:
0.08 mL
Explanation:
The solution of the skin test has a concentration of 0.2% (w/v), which means that there are 0.2 g of the antigen per 100 mL of the solution. If a new solution will be done using it, then this solution will be diluted, and the mass of the antigen added must be the same in the volume taken and at the diluted solution.
The mass is the concentration (in g/mL) multiplied by the volume of the solution (in mL), so, if m is the mass, C the concentration, V the volume, 1 the initial solution, and 2 the diluted:
m1 = m2
C1*V1 = C2*V2
Where
C1 = 0.2 g/100 mL = 0.002 g/mL
V1 = ?
C2 = 0.04 mg/mL = 0.00004 g/mL
V2 = 4 mL
0.002*V1 = 0.00004*4
V1 = 0.08 mL
<u>Complete Question:</u>
Which of the following is not a characteristic of electromagnetic waves?
a. they can travel through a vacuum.
b. they can travel at various speeds through any one material.
c. they can be refracted.
d. they can be reflected.
<u>Correct Option:</u>
"They can travel at various speeds through any one material" is not a characteristic of electromagnetic waves.
<u>Explanation:</u>
It is a form of energy generated by interference from the oscillating magnetic and electric recorded. So we may conclude that it is created by moving electric charged particles through the vacuum so matter. This is a wave in which the two vectors vibrate each other perpendicularly and in the direction of the wave. Electromagnetic waves which involve gamma-rays, x-rays, ultraviolet rays, infrared-rays, microwaves and radio-waves can be featured by:
- They may pass through the vacuum.
- They are allowed to move through the matter and are reflectable.
- They can pass through all of the material at the same pace. This means there is still constant speed of light, which is, they can be refracted.
Answer:- The charge is +2.
Explanations:- Z stands for atomic number. The Z is given as 25 means the atomic number of the element is 25. It has 23 electrons. For a neutral atom the number of electrons is same as the atomic number. Since the number of electrons is less than atomic number, the atom must have lost the electrons.
Number of electrons lost = 25 - 23 = 2
If the element lost electrons then it has positive charge. As, the electrons are lost, the charge is +2.
