3
- it is a gas so not 2
- 1 is a diatomic molecule (both atoms the same)
- 4 only has 2 atoms joined in each
<span>Answer: a mixture.
</span><span>Justification:</span>
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</span><span>1) Pure substances have a definite chemical formula: the same kind of atoms with the same fixed ratios and chemical bonds. Therefore, the percents of each element do not varye.
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2) Elements and compounds are pure substaces. For example, Fe, Mg, Ti, are elements, and CO₂, CO, H₂CO₃ are compounds. Each of them will have always the same kind of atoms, in the same ratio and with the same chemcial bonds. Therefore the percents of the elements do not varye.
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<span>3) Mixtures are formed by the physical combination (not chemical bonds) of different elements or compounds in variable proportions. As indicated, this describes the material bronze, in virtue of the variation of its composition. Other examples of mixtures are solutions (like brines), air, ocean water, and milk: different brines, different oceans and different milk have different contents of elements or compounds.
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Answer:
First, let's express pressure P in Pa and volume V in m3:
⇒P=175 kPa
⇒P=1.75×105 Pa
and
⇒V=275 ml
⇒V=2.75×10−4 m3
Then, let's solve the ideal gas law PV=nRT for temperature T:
⇒PV=nRT
⇒T=PVnR
Substituting the appropriate values into the equation:
⇒T=1.75×105×2.75×10−40.80×8.314 K
⇒T=48.1256.6512 K
∴T≈7.24 K
Therefore, the temperature is around 7.24 K.
I wanna say milliliter but I’m not sure
Answer:
The answer is A.) age
Explanation:
The older the sample, the more the sample will have decayed, and the less radioactive it will be.