After putting stuff through google and some calculators, I’d say the answer is C.
Answer:
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No; the sample could not be aluminum;
since the density of aluminum, " 2.7 g/cm³ " , is NOT close enough to the density of the sample, " 3.04 g/cm³ " .
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Explanation:
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Density is expressed as "mass per unit volume" ;
in which:
"mass, "m", is expressed in units of "g" (grams); and:
"Volume, "V", is expressed in units of "cm³ " (such as in this problem); or in units of "mL" ;
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{Note the exact conversion: " 1 cm³ = 1 mL " .}.
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The formula for density: D = m/V ;
Given: The density of aluminum is: 2.7 g/cm³.
Given: A sample has a mass of 52.0 g ; and Volume of 17.1 cm³ ; could it be aluminum?
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Let us divide the mass of the sample by the volume of the sample;
by using the formula:
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D = m / V ;
and see if the value is at, or very close to "2.7 g/cm³ ".
If it is, then it could be aluminum.
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The density for the sample:
D = (52.0 / 17.1) g/cm³ = 3.0409356725146199 g/cm³ ;
→round to "3 significant figures" ;
= 3.04 g/cm³ .
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No; the sample could not be aluminum; since the density of aluminum,
"2.7 g/cm³ " is NOT close enough to the density of the sample,
"3.04 g/cm³ " .
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1. Ca → Element
2. Proton → positive
3. H2O → compound
4. Fission → nuclear decay
5. Fusion → Nuclear synthesis
6. η → Neutron
7. e → electron
8. Atomic number → no of protons in nucleus.
Explanation
1. Ca (Calcium):
Calcium is an element with the atomic number of 20. It is an alkaline earth metal. The 99% of calcium is found in our bodies, in bones, teeth.
2. Proton:
Proton is a subatomic particle and it holds the positive charge. Proton is present in the nucleus of the atom.
3. H2O (water):
Water is a chemical compound and it's chemical formula is H2O. It's called compound as it contains 2 hydrogen and 1 oxygen atoms bonded together through the covalent bond.
4. Fission:
Fission is a process in which large massive unstable nucleus splits into the smaller, less heavier and stable nuclei. The energy is re;eased in the form of radiations during this process. It's called as the radioactive decay.
5. Fusion:
Fusion is opposite of the fission reaction. As in this case the two nuclei combines to form a single large nucleus. That's why it is a nuclear synthesis process.
6. η neutron:
Neutron is a subatomic particle and it is a neutral particle which is located inside the nucleus. n is a symbol used for the neutron.
7. e Electron:
The symbol for electron is e. It's a subatomic particle with negative charge. It is found in the orbits around the nucleus.
8. Atomic Number:
Atomic number is defined as the number of protons in the nucleus of an atom. IT is represented by Z.
It is D. X rays have a shorter wavelength than microwaves.
The best answer would be the 4th choice. "They help scientists explain concepts that are difficult to observe, this also covers the first answer which helps the scientist to answer complex questions. A scientific model is not used prove scientific laws as they may not always have all the data to prove so, instead it is used to allow them to explain better concepts revolving around science through research and may also allow them to predict results based on the accumulation of data and analyzing the trend of this resulting information.