Reaction: 2K₍s₎ + 2H₂O₍l₎ → 2KOH₍aq₎ + H₂₍g₎.
K - potassium.
H₂O - water.
KOH - potassium-hydroxide.
H₂ - hydrogen.
s - solid phase.
l - liquid.
aq - disolves in water.
g - gas.
Reaction is exothermal (release of energy) and potassium burns a purple flame. H<span>ydrogen released during the reaction reacts with </span>oxygen<span> and ignites.</span><span>
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Answer:
It is both accurate and precise.
Explanation:
Precision and accuracy are two different terms used to describe data or measurements. Accuracy refers to how close a set of measurements/experimental values is to an accepted or correct value while Precision refers to how close a series of experimental values are to one another.
In the given set of data in the question below, the Correct Value is 59.2 while the experimental values are as follows;
Trial 1: 58.7
Trial 2: 59.3
Trial 3: 60.0
Trial 4: 58.9
Trial 5: 59.2
Based on comparison, it can be observed that these experimental values are close to the correct value (59.2). Hence, they are said to be ACCURATE. Also, the experimental values are close to one another, hence, they are said to be PRECISE.
Therefore, the data set is both accurate and precise.
Answer:
You may be referring to the gas that makes up 21% of the earth's atmosphere, which is oxygen.
Explanation:
According to NASA, the gases in Earth's atmosphere include:
Nitrogen — 78 percent
Oxygen — 21 percent
Argon — 0.93 percent
Carbon dioxide — 0.04 percent
(Trace amounts of neon, helium, methane, krypton and hydrogen, as well as water vapor)