Answer is: 2. atomic number.
Atomic number is unique and defines an element. Atomic number (Z) is total number of protons in an atom.
For example, nitrogen atom (N-14) has 7 protons (p⁺), 7 electrons (e⁻) and 7 neutrons (n°). Protons (positive charge) and neutrons are in the nucleus of atom, electrons (negative charge) are bound to the nucleus in spherical shells. Nitrogen is an element with atomic number 7. Mass number (A) is the total number of protons and neutrons in a nucleus. Nitrogen mass number is 14 (A = p⁺ + n°; A = 14).
☃️ Chemical formulae ➝ 
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<u>How to find?</u></h3>
For solving this question, We need to know how to find moles of solution or any substance if a certain weight is given.
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<u>Solution:</u></h3>
Atomic weight of elements:
Ca = 40
C = 12
O = 16
❍ Molecular weight of
= 40 + 12 + 3 × 16
= 52 + 48
= 100 g/mol
❍ Given weight: 10 g
Then, no. of moles,
⇛ No. of moles = 10 g / 100 g mol‐¹
⇛ No. of moles = 0.1 moles
☄ No. of moles of Calcium carbonate in that substance = <u>0.1 moles</u>
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Answer:
The false statement is: 3. Because liquid water and liquid carbon tetrachloride do not mix, neither do their vapors
Explanation:
Gas is a state of matter, that has <u>less density than liquids and solids</u>. The gaseous particles have low intermolecular forces and thus they can move freely.
It is a very <u>compressible fluid</u> that has no fixed shape. Gas occupies the whole container in which it is stored, thus taking the shape of the container. Therefore, <u>the volume of the gas is equal to the volume of the container.</u>
<u>Polar liquid like water (H₂O) and nonpolar liquid like carbon tetrachloride, are immiscible. However, in the gaseous state, their vapors form a homogeneous mixture.</u>
<span>renewable resources are used primarily to produce electricity include wind and hydro-electric power. they require large mechanical structures e.g. wind turbine and water dam in order to generate electric energy. Therefore they are not appropriate for home use.
</span><span>renewable resources are readily used as heat sources for homes include solar-water heating system in which water is heated by sunlight and circulated around the house. Wood burning for heat can also be considered a renewable resource as long as the wood comes from a sustainable logging cycle.</span>
Answer:
CH4 - Methane
B2Si - Diboron monosilicide
N2O5 - Dinitrogen pentoxide
CO2 - Carbon dioxide
Explanation:
When it comes to naming covalent compounds, there are several rules.
The name is derived based on the formula. For example, N2O5. The first element is nitrogen. To the name of the element, you add the prefix that tells us how many of its atoms are in the compound. In this case, there are two atoms, which means that the prefix will be <em>di</em>- (dinitrogen). The second element is oxygen. You are supposed to take only the root of the second element's name and then add the prefix denoting the number of its atoms and the suffix <em>-ide</em> (pentoxide). This is how we'll get dinitrogen pentoxide.
The only exception is methane (CH4), which is an organic compound. Organic compounds are named using the IUPAC nomenclature.
