Volume of Hydrogen V1 = 351mL
Temperature T1 = 20 = 20 + 273 = 293 K
Temperature T2 = 38 = 38 + 273 = 311 K
We have V1 x T2 = V2 x T1
So V2 = (V1 x T2) / T1 = (351 x 311) / 293 = 372.56
Volume at 38 C = 373 ml

6 0

3 years ago

In the following overall chemical reaction, aluminum displaces chromium from chromium(III) oxide and forms aluminum oxide.

mafiozo [28]

Answer:

Change in enthalpy for the reaction is -536 kJ

Explanation:

Overall chemical reaction can be represented a summation of two given elementary steps with slight modification.
Take reaction (1a) and divide stoichiometric coefficients by 2
Take reverse reaction (2a) and divide stoichiometric coefficient by 2
Then add these two modified elementary steps to get overall chemical reaction
$\Delta H$ is an additive property. hence value of $\Delta H$ will be changed in accordance with modification

$2Al+\frac{3}{2}O_{2}\rightarrow Al_{2}O_{3}.....\Delta H_{1}=\frac{-3351.4}{2}kJ=-1675.7kJ$

$Cr_{2}O_{3}\rightarrow 2Cr+\frac{3}{2}O_{2}....\Delta H_{2}=\frac{2279.4}{2}kJ=1139.7kJ$

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$2Al+Cr_{2}O_{3}\rightarrow 2Cr+Al_{2}O_{3}....\Delta H=\Delta H_{1}+\Delta H_{2}=-1675.7+1139.7kJ=-536kJ$

6 0

3 years ago

For a tablet containing 500. mg of vitamin C, calculate how many ml of 0.095 M NaOH is required to reach the equivalence point.

Gala2k [10]

Answer:

mL of NaOH required =29.9mL

Explanation:

Let us calculate the moles of vitamin C in the tablet:

The molar mass of Vitamin C is 176.14 g/mole

$moles=\frac{mass}{molarmass}=\frac{500mg}{176.14}=\frac{0.5}{176.14}=0.0028$

Thus we need same number of moles of NaOH to reach the equivalence point.

For NaOH solution:

$moles=MolarityXvolume=0.095Xvolume$

$0.00283=0.095Xvolume$

$volume=0.0299L=29.9mL$

7 0

3 years ago

2Fe2O3+3C_4Fe+3 CO2 how many moles of Carbon are needed to produce 1.9 moles of iron (Fe)?​

2Fe2O3+3C_4Fe+3 CO2 how many moles of Carbon are needed to produce 1.9 moles of iron (Fe)?