Answer:
quartz (SiO2)n
Explanation:
Melting point is defined as the temperature or point at which the substances change its state from solid to liquid.
Quartz (SiO2)n has high melting point than O2 because Quartz (SiO2)n is found in the form of hard, crystalline mineral that is made up of silicon and oxygen atoms having strong covalent bonds between all the atoms. So, a lot of energy is required to break the bond between the atoms and it has a high melting point.
Hence, the correct answer is quartz (SiO2)n.
<span>It is known
that acids compounds contains hydrogen and produces hydrogen ion in water. A binary
acid however is an acid that have two elements, one of the element has a
hydrogen attached to it. Examples of binary acids are hydrogen fluoride (HF),
hydrogen bromide (HBr) and hydrogen sulfide (H2S). In naming a binary acid, it
has two rules; one, as pure compounds and two, as acid solutions. For pure
compounds, start with the name ‘hydrogen’ and end the anion name with ‘-ide’. For
acidic compounds, start with ‘hydro-‘, end the anion with ‘-ic’ and add ‘acid’.</span>
<span>Answer: 100 ml
</span>
<span>Explanation:
1) Convert 1.38 g of Fe₂S₃ into number of moles, n
</span>i) Formula: n = mass in grass / molar mass
<span>
ii) molar mass of </span><span>Fe₂S₃ =2 x 55.8 g/mol + 3 x 32.1 g/mol = 207.9 g/mol
</span>
iii) n = 1.38 g / 207.9 g/mol = 0.00664 moles of <span>Fe₂S₃
</span>
<span>2) Use the percent yield to calculate the theoretical amount:
</span>
<span>65% = 0.65 = actual yield/ theoretical yield =>
</span>theoretical yield = actual yield / 0.65 = 0.00664 moles / 0.65 = 0.010 mol <span>Fe₂S₃</span><span>
3) Chemical equation:
</span>
<span> 3 Na₂S(aq) + 2 FeCl₃(aq) → Fe₂S₃(s) + 6 NaCl(aq)
4) Stoichiometrical mole ratios:
</span>
<span>3 mol Na₂S : 2 mol FeCl₃ : 1 mol Fe₂S₃ : 6 mol NaCl
5) Proportionality:
</span>2moles FeCl₃ / 1 mol Fe₂S₃ = x / 0.010 mol Fe₂S₃
<span>
=> x = 0.020 mol FeCl₃
6) convert 0.020 mol to volume
</span>
<span>i) Molarity formula: M = n / V
</span>
<span>ii) V = n / M = 0.020 mol / 0.2 M = 0.1 liter = 100 ml
</span>
Answer:
A conclusion derived from evidence and logical reasoning
Explanation:
. In an alkane molecule, all the atoms will be bonded through single bonds.
. An alkene molecule will have atleast one double bond between two carbon atoms.
. An alkyne will have atleast one triple bond between two carbon atoms.