Answer:
Ice melting is a physical change. Physical changes are changes which affect the form of a chemical substance, but not its chemical composition. Certain factors, such as, temperature, contribute to the melting of ice, but it will be classified as a physical change, because the number of molecules present in the water does not change.
Explanation:
Answer:
The total energy change, ΔE, in kilojoules = -61.93 kJ
Explanation:
Relationship between ΔH, ΔE and work done is given by first law of thermodynamics.
ΔE = ΔH - PΔV
Where,
ΔH = Change in enthalpy
ΔE = Change in internal energy
PΔV = Work done
Given that,
ΔH = -75.0 kJ = -75000 J
P = 43.0 atm
ΔV = Final volume - initial volume
= (2.00 - 5.00) = -3.00 L
PΔV = 43 × (-3.00) = -129 L atm
1 L atm = 101.325 J
-129 L atm = 129 × 101.325 = -13071 J
So ,
ΔE = ΔH - PΔV
= (-75000 J) - ( -13071 J)
= -75000 J + 13071 J
= -61929 J
Total energy change, ΔE = -61.929 kJ
the answer is C because it has no water there will be nothing to boil and odor has nothing to do with hydrogen
I hope this helps! :)
-Ayden
That's a lot of conversions...
107*7 = 749km in one week
749/1.6 = 468.125 miles
468.125/39 = <span>12.0032051282 gallons of fuel needed
</span>1 gallon = 4.54609 litres
1.1(Cost per litre)*4.54609(Number of litres per gallon)*12.0032051282(Number of gallons needed) = <span>60.0244158814 euros cost per week
</span>60.0244158814 * 1.26 = <span>75.6307640105 dollar cost per week
</span>$75.63
Answer:
- <em>There are </em><u><em>4 moles</em></u><em> of chloride ions in 2 moles of calcium chloride.</em>
Explanation:
Start by writing the chemical formula of calcium chloride.
The suffix -ide in chloride means that chlorine is working as the ion Cl⁻, this is with oxidation state -1.
Calcium, being an alkaline earth metal, uses oxidation state +2, Ca²⁺
Then, two atoms of Cl are combined with one atom of calcium, because in this way each Cl atom will accept one electron from a Ca atom, which will donate its two valence electrons.
That is indicated in the chemical formula with subscripts: <u><em>CaCl₂</em></u>, meaning that each formula-unit of calcium chloride has 2 ions of chlorine and 1 ions of calcium, or twice the number of moles of chloride ion.
- 1 mol CaCl₂ : 1 mol Ca⁺ : 2 mol Cl⁻
⇒ 2 mol CaCl₂ : 2 mol Ca⁺ : 4 mol Cl⁻
Hence, there are 4 moles of chloride ions in 2 moles of calcium chloride.
