Explanation:
1.
Given parameters:
Frequency of the radiation = 8.4 x 10¹⁴Hz
Unknown:
Energy of the wave = ?
Solution:
The energy of a wave is given by the expression below;
E = hf
E is the energy
h is the Planck's constant = 6.63 x 10⁻³⁴m²kg/s
f is the frequency
Now insert the parameters and solve;
E = 6.63 x 10⁻³⁴m²kg/s x 8.4 x 10¹⁴Hz
E = 5.57 x 10¹ x 10⁻²⁰J
E = 5.57 x 10⁻¹⁹J
2.
Given parameters:
Wavelength = 2.13 x 10⁻¹³m
Unknown:
Frequency of the wave = ?
Solution:
The frequency of a wave can be determined using the expression;
C = f∧
C is the speed of light = 3 x 10⁸m/s
f is the frequency
∧ is the wavelength
f = 
= 
= 1.41 x 10²¹hz
Answer: Fireworks exploding is a chemical change.
Explanation: Lighting gunpowder, and making the explosion is a chemical change.
This compound is Boron selenate. Molar mass of B2(SeO4)3 is 450.4948 g/mol.
Answer:
a= <em>In scientific notation</em>
6.96000×10⁵ Km
b =<em>In expanded notation</em>
0.00019 mm
Explanation:
Given data:
Radius of sun = 696000 Km
size of bacterial cell = 1.9 ×10⁻⁴ mm
Radius of sun in scientific notation = ?
Size of bacterial cell in expanded notation = ?
Solution:
Scientific notation is the way to express the large value in short form.
The number in scientific notation have two parts.
. The digits (decimal point will place after first digit)
× 10 ( the power which put the decimal point where it should be)
for example the number 6324.4 in scientific notation will be written as = 6.3244 × 10³
Radius of sun:
696000 Km
<em>In scientific notation</em>
6.96000 × 10⁵ Km
The expanded notation is standard notation of writing the numerical values which is normal way. The numbers are written as they are, without the power of 10.
Size of bacterial cell:
1.9 ×10⁻⁴ mm
<em>In expanded notation</em>
1.9/ 10000 = 0.00019 mm
