Explanation:
1) Initial mass of the Cesium-137=
= 180 mg
Mass of Cesium after time t = N
Formula used :
Half life of the cesium-137 =
= initial mass of isotope
N = mass of the parent isotope left after the time, (t)
= half life of the isotope
= rate constant

Now put all the given values in this formula, we get
Mass that remains after t years.

Therefore, the parent isotope remain after one half life will be, 100 grams.
2)
t = 70 years


N = 35.73 mg
35.73 mg of cesium-137 will remain after 70 years.
3)


N = 1 mg
t = ?

t = 224.80 years ≈ 225 years
After 225 years only 1 mg of cesium-137 will remain.
Answer:
double replacement
Explanation:
The reaction shown is a double replacement reaction.
It is also known as double decomposition or metathesis reaction.
In such a reaction, there is an actual exchange of partners to form new compounds.
One of the following is the driving force for such reaction:
- formation of an insoluble compound or precipitate
- formation of water or any other non-ionizing compound
- liberation of a gaseous product.
Answer:
0.6743 M
Explanation:
HC₂H₃O₂ + NaOH → NaC₂H₃O₂ + H₂O
First we <u>calculate how many NaOH moles reacted</u>, using the <em>definition of molarity</em>:
- Molarity = moles / volume
- moles = Molarity * volume
- 0.4293 M * 39.27 mL = 16.86 mmol NaOH
<em>One NaOH moles reacts with one acetic acid mole</em>, so <u>the vinegar sample contains 16.86 mmoles of acetic acid as well</u>.
Finally we <u>calculate the concentration (molarity) of acetic acid</u>:
- 16.86 mmol HC₂H₃O₂ / 25.00 mL = 0.6743 M
Transverse waves have motion perpendicular to velocity, while longitudinal waves have motion parallel to velocity.
Explanation:
The correct option of all is that transverse waves have motion perpendicular to velocity while longitudinal waves have motion parallel to velocity.
A wave is a disturbance that transmits energy from one point to another. There several types of waves like sound, electromagnetic , ocean waves etc.
- Waves can be classified as either longitudinal or transverse waves based on the direction through which they are propagated.
- Longitudinal waves are waves propagated parallel to the source of velocity.
- An example is sound waves and seismic p-waves.
- They have series of rarefaction and compression along their path.
- Transverse waves are propagated perpendicular to their source.
- An example is electromagnetic waves in which electrical and magnetic fields vibrates perpendicularly.
learn more:
Electromagnetic radiation brainly.com/question/6818046
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