It's K since K and Na are in the same family
Ultraviolet has more energy. You can tell because it has a shorter wave. The longer the wave is on the electromagnetic spectrum the less energy is stored.
Answer:
Element
Explanation:
An element is substance that is composed of only one kind of atom and can not be separated into simpler substances or converted into another substance by chemical processes.
Chemical elements are found in the periodic table. Examples of chemical elements include; sodium potassium, phosphorus, hydrogen etc.
Answer: students are the dependent variable and the cartoon are the independent variable
Explanation: because the cartoon are being the same ever and the opinion of the students is what changes
Answer:
a. 0.31 g
Explanation:
- It is known that the decay of a radioactive isotope isotope obeys first order kinetics.
- Also, it is clear that in first order decay the half-life time is independent of the initial concentration.
- Half-life time is the time needed for the reactants to be in its half concentration.
- If reactant has initial concentration [A₀], after half-life time its concentration will be ([A₀]/2).
- The half-life time of the substance = 14 days.
<em>So, 70 days represent (70 days/ 14 days = 5.0 half-lives).</em>
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- So, the substance will decay:
10 g → (first half-life = 14 days) 5 g → (second half-life = 28 days) 1.5 g → (third half-life = 42 days) 1.25 g → (fourth half-life = 56 days) 0.625 g → (fifth half-life = 70 days) 0.3125 g.
<em>So, the right choice is: a. 0.31 g.</em>
