Answer:
Explanation:
Isotopes are atoms of elements that have the same atomic number but different mass number hence ISOTOPY. Radioactive Isotopes on the other hand are unstable as they either undergo Alpha decay, beta decay or gamma decay compared to stable isotopes.
Radioactive elements decay at varyinf rates as such the rate of radioactive decay is used in the characterization of radioactive element and mostly expressed in terms of the half life of the radioactive elements.
Half life is the time taken for half of the total atoms of an elements to decay into half of its initial sizes. for example, the half life of radium-226 is 1622 years, it implies that if we have 1000000 radium atoms at the beginning, then at the end of 1622years, 500000 would have disintegrated. These phenomenon can never be experienced by stable isotopes as such they can not be used in carbon dating techniques. reason why uranium-238 is mostly and commonly used in the earth crust to estimate the ages of rocks because it has a half life of 4.5 x 10^9 years.
And also, the radioactive isotopes of most common light element are short, they have very short half life (few days or weeks) and they decay rapidly to vanshing point, as such, they are not found in nature to any reasonable extent.
The atomic mass is equal to the number of neutrons, plus the number of protons, in the nucleus of the atom
Hello!
Before I can answer your question we need to know the different types of chemical reactions that can occur:
- Single Replacement
- Double Replacement
- Synthesis
- Decomposition
- Combustion
Combustion is an answer that can usually be ruled out unless oxidation is occuring in the chemical equation (hyrdrogen occuring with oxygen to react)
Synthesis reaction, also known as a Combination reaction, is when the reactants combine to form a single product.
Decompostion is when a single reactant is deconstructed to form multiple products, or the opposite of Synthesis.
With these definitions alone, since they are opposite types of reactions, the answer would be Synthesis and Decomposition reactions !
Hope this helps and if you need anymore clarification feel free to ask.
Answer:
λ = 0.38 ×10⁻⁹ m
Explanation:
Given data:
Wavelength of xray = ?
Frequency of xray = 7.8 ×10¹⁷ Hz
Solution:
Formula:
Speed of light = wavelength × frequency
speed of light = 3×10⁸ m/s
Now we will put the values in formula.
3×10⁸ m/s = λ × 7.8 ×10¹⁷ Hz
λ = 3×10⁸ m/s / 7.8 ×10¹⁷ Hz
Hz = s⁻¹
λ = 3×10⁸ m/s / 7.8 ×10¹⁷s⁻¹
λ = 0.38 ×10⁻⁹ m
Answer:
Two conversion factors:
Explanation:
You can create two possible <em>conversion factors</em>, one to convert from mL to L, and one to convert from L to mL
<u />
<u>a) From mL to L</u>
To convert mL to L you need to multiply by a conversion factor that has mL on the denominator and L in the numerator.
Your starting point is: 
Then, divide both sides by 1,000mL (this will be on the denominator of the fraction);
<u>b) From L to mL</u>
Divide both sides by 1 L:
