Why aren't sharks extinct?

Calculate the mass of CaCl2•2H2O required to make 100.0 mL of a 0.100 M solution. Each of the calculations below will take you t

Zolol [24]

Answer:

The mass is 1.4701 grams and the moles is 0.01.

Explanation:

Based on the given question, the volume of the solution is 100 ml or 0.1 L and the molarity of the solution is 0.100 M. The moles of the solute (in the given case calcium chloride dihydride (CaCl2. H2O) can be determined by using the formula,

Molarity = moles of solute/volume of solution in liters

Now putting the values we get,

0.100 = moles of solute/0.1000

Moles of solute = 0.100 * 0.1000

= 0.01 moles

The mass of CaCl2.2H2O can be determined by using the formula,

Moles = mass/molar mass

The molar mass of CaCl2.2H2O is 147.01 gram per mole. Now putting the values we get,

0.01 = mass / 147.01

Mass = 147.01 * 0.01

= 1.4701 grams.

4 0

3 years ago

Combustion analysis of toluene, a common organic solvent, gives 3.52 mg of co2 and 0.822 mg of h2o. if the compound contains onl

IRISSAK [1]

C7H8 First, lookup the atomic weight of all involved elements Atomic weight of carbon = 12.0107 Atomic weight of hydrogen = 1.00794 Atomic weight of oxygen = 15.999 Then calculate the molar masses of CO2 and H2O Molar mass CO2 = 12.0107 + 2 * 15.999 = 44.0087 g/mol Molar mass H2O = 2 * 1.00794 + 15.999 = 18.01488 g/mol Now calculate the number of moles of each product obtained Note: Not interested in the absolute number of moles, just the relative ratios. So not going to get pedantic about the masses involved being mg and converting them to grams. As long as I'm using the same magnitude units in the same places for the calculations, I'm OK. moles CO2 = 3.52 / 44.0087 = 0.079984 moles H2O = 0.822 / 18.01488 = 0.045629 Since each CO2 molecule has 1 carbon atom, I can use the same number for the relative moles of carbon. However, since each H2O molecule has 2 hydrogen atoms, I need to double that number to get the relative number of moles for hydrogen. moles C = 0.079984 moles H = 0.045629 * 2 = 0.091258 So we have a ratio of 0.079984 : 0.091258 for carbon and hydrogen. We need to convert that to a ratio of small integers. First divide both numbers by 0.079984 (selected since it's the smallest), getting 1: 1.140953 The 1 for carbon looks good. But the 1.140953 for hydrogen isn't close to an integer. So let's multiply the ratio by 1, 2, 3, 4, ..., etc and see what each new ratio looks like (Effectively seeing what 1, 2, 3, 4, etc carbons look like) 1 ( 1 : 1.140953) = 1 : 1.140953 2 ( 1 : 1.140953) = 2 : 2.281906 3 ( 1 : 1.140953) = 3 : 3.422859 4 ( 1 : 1.140953) = 4 : 4.563812 5 ( 1 : 1.140953) = 5 : 5.704765 6 ( 1 : 1.140953) = 6 : 6.845718 7 ( 1 : 1.140953) = 7 : 7.986671 8 ( 1 : 1.140953) = 8 : 9.127624 That 7.986671 in row 7 looks extremely close to 8. I doubt I'd get much closer unless I go to extremely high integers. So it looks like the empirical formula for toluene is C7H8

7 0

3 years ago

A gas used to extinguish fires is composed of 75 % CO2 and 25 % N2. It is stored in a 5 m3 tank at 300 kPa and 25 °C. What is th

tatyana61 [14]

Answer : The partial pressure of the $CO_2$ in the tank in psia is, 32.6 psia.

Explanation :

As we are given 75 % $CO_2$ and 25 % $N_2$ in terms of volume.

First we have to calculate the moles of $CO_2$ and $N_2$ .

$\text{Moles of }CO_2=\frac{\text{Volume of }CO_2}{\text{Volume at STP}}=\frac{75}{22.4}=3.35mole$

$\text{Moles of }N_2=\frac{\text{Volume of }N_2}{\text{Volume at STP}}=\frac{25}{22.4}=1.12mole$

Now we have to calculate the mole fraction of $CO_2$ .

$\text{Mole fraction of }CO_2=\frac{\text{Moles of }CO_2}{\text{Moles of }CO_2+\text{Moles of }N_2}$

$\text{Mole fraction of }CO_2=\frac{3.35}{3.35+1.12}=0.75$

Now we have to calculate the partial pressure of the $CO_2$ gas.

$\text{Partial pressure of }CO_2=\text{Mole fraction of }CO_2\times \text{Total pressure of gas}$

$\text{Partial pressure of }CO_2=0.75mole\times 300Kpa=225Kpa=225Kpa\times \frac{0.145\text{ psia}}{1Kpa}=32.625\text{ psia}$

conversion used : (1 Kpa = 0.145 psia)

Therefore, the partial pressure of the $CO_2$ in the tank in psia is, 32.6 psia.

3 0

3 years ago

What weight of sodium hydroxide will react with 73 gram of hydrogen chloride gas at NTP to Produce 117.0 gram of Nacl and 36 gra

Wewaii [24]

Let's write the equation

$\\ \sf\longmapsto {NaOH\atop ?}+{HCl\atop 73g}\longrightarrow {NaCl\atop 117g}+{H_2O\atop 36g}$

According to law of conservation of mass .

Mass of products=Mass of reactants

Let required value be x

$\\ \sf\longmapsto x+73=117+36$

$\\ \sf\longmapsto x+73=153$

$\\ \sf\longmapsto x=153-73$

$\\ \sf\longmapsto x=80g$

8 0

3 years ago

Read 2 more answers

Uv gel enhancements rely on ingredients from the monomer liquid and ________ chemical family.

pishuonlain [190]

UV gel enhancements rely on ingredients from the monomer liquid and polymer powder chemical family. The chemicals from the polymer powder family can absorb and retain extremely large amounts of a liquid relative to their own mass. Water-absorbing polymers, can absorb aqueous solutions through hydrogen bonding with water molecules.

6 0

3 years ago