Answer:
31.5 mL of a 2.50M NaOH solution
Explanation:
Molarity (M) is an unit of concentration defined as moles of solute (In this case, NaOH), per liter of solvent. That is:
Molarity = moles solute / Liter solvent
If you want to make 525mL (0.525L) of a 0.150M of NaOH, you need:
0.525L × (0.150mol / L) = <em>0.07875 moles of NaOH</em>
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If you want to obtain these moles from a 2.50M NaOH solution:
0.07875mol NaOH × (1L / 2.50M) = 0.0315L = <em>31.5 mL of a 2.50M NaOH solution</em>
3.44x10^2
you move the decimal over to get a single digit number with change. The number of times you move the decimal is the number for the 10 power
Answer:
B
Explanation:
A chemical change occurred, and this caused the liquid’s physical properties to change.
when we read her experiment we can see that color changed to blue, it is because new products are formed. And the temperature cause this.
Let us assume propane was the fuel
C3H8(g) + 5O2(g) ---> 3CO2(g) + 4H2O(g) = 2217kJ
1 mole ofpropane produces 3 moles of CO2
heat absorbed by pork = 0.11 x 2217
= 243.87 kJ/mol
number of moles of propane = 1700kJ / 243.87 kJ/mol
= 6.971 moles
1 mole of C3H8 = 3 moles ofCO2
6.971 moles of C3H8 = ?
3 x 6.971 = 20.913 moles of CO2
Convert to grams
mass = MW x mole
= 44 x 20.913
= 920.172g of CO2 emitted
The formula of Iron(III) oxide is Fe2O3
In order to calculate the mass of iron in a given sample of iron(III) oxide, we must first know the mass percentage of iron in iron(III) oxide. This is calculated by:
[mass of iron in one mole of iron(III) oxide/ mass of one mole of iron(III) oxide] * 100
= [(moles of iron * Mr of iron) / (moles of Iron * Mr of Iron + moles of Oxygen * Mr of Oxygen)] * 100
= [(2 * 56) / (2 * 56 + 3 * 16)] * 100
= (112 / 160) * 100
= 70%
Thus, in a 100g sample, the weight of iron will be:
100 * 70%
= 70 grams
