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3 years ago

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Number 72 I need help

1 answer:

Mashutka [201]3 years ago

7 0

A. Cs - 55 electrons, 55 protons, 77 neutrons
B. Co - 27 electrons, 22 protons, 32 neutrons
C. Tm - 69 electrons, 69 protons, 94 neutrons
D. Zn - 30 electrons, 30 protons, 40 neutrons

For any neutral atom, protons = electrons = atomic number. Neutrons = atomic mass - atomic number.

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What is Cytokine Release Syndrome (CRS)

laila [671]

Answer:

Cytokine release syndrome (CRS) is an acute systemic inflammatory syndrome characterized by fever and multiple organ dysfunction that is associated with chimeric antigen receptor (CAR)-T cell therapy, therapeutic antibodies, and haploidentical allogeneic transplantation.

Explanation:

4 0

3 years ago

Mixtures of benzene and cyclohexane exhibit ideal behavior. A solution was created containing 1.5 moles of liquid benzene and 2.

goblinko [34]

Answer:

Vapour pressure of cyclohexane at 50°C is 490torr

Vapour pressure of benzene at 50°C is 90torr

Explanation:

Using Raoult's law, pressure of a solution is defined by the sum of the product sbetween mole fraction of both solvents and pressure of pure solvents.

$P_{solution} = X_{A}P^0_{A}+X_{B}P^0_{B}$

In the first solution:

$X_{cyclohexane}=\frac{2.5mol}{2.5mol+1.5mol} =0.625$

$X_{benzene}=\frac{1.5mol}{2.5mol+1.5mol} =0.375$

$340torr = 0.625P^0_{A}+0.375P^0_{B}$ <em>(1)</em>

For the second equation:

$X_{cyclohexane}=\frac{3.5mol}{3.5mol+1.5mol} =0.700$

$X_{benzene}=\frac{1.5mol}{3.5mol+1.5mol} =0.300$

$370torr = 0.700P^0_{A}+0.300P^0_{B}$ <em>(2)</em>

Replacing (2) in (1):

$340torr = 0.625P^0_{A}+0.375(1233.3-2.333P^0_{A})$

$340torr = 0.625P^0_{A}+462.5-0.875P^0_{A}$

-122.5torr = -0.250P°A

$P^0_{A} = 490 torr$

<em>Vapour pressure of cyclohexane at 50°C is 490torr</em>

And for benzene:

$370torr = 0.700*490torr+0.300P^0_{B}$

$P^0_{B}=90torr$

<em>Vapour pressure of benzene at 50°C is 90torr</em>

3 0

3 years ago

Whats the number of moles of O2(g) needed to completely react with 8 moles of CO(g).

slava [35]

A mole of CO2 = 2 moles of O2
8 CO moles x 2 =

16 moles

7 0

3 years ago

Gaseous methane CH4 reacts with gaseous oxygen gas O2 to produce gaseous carbon dioxide CO2 and gaseous water H2O. What is the t

Murrr4er [49]

Answer:

50.8 g

Explanation:

Equation of reaction.

$CH_4 + 2O_2 \to CO_2 + 2H_2O$

From the given information, the number of moles of methane = mass/ molar mass

= 15.4 g / 16.04 g/mol

= 0.960 mol

number of moles of oxygen gas = 90.3 g / 32 g/ mol

= 2.82 mol

Since 1 mol of methane requires 2 moles of oxygen

Then 0.960 mol of methane will require = 0.960 mol × 2 = 1.92 mol of oxygen gas

Thus, methane serves as a limiting reagent.

2.82 mol oxygen gas will result in 2.82 moles of water

So, the theoretical yield of water = moles × molar mass

= 2.82 mol × 18.01528 g/mol

= 50.8 g

8 0

3 years ago

from the balanced equation we see that h20 is 1 to 1 mole ratio the number of moles of acid and base. What is the number of mole

forsale [732]

Answer:

0.0498 mol

Explanation:

Number of moles = concentration in mol/L × volume in L

Concentration = 1 M = 1 mol/L

Volume = 49.8 mL = 49.8/1000 = 0.0498 L

Number of moles = 1×0.0498 = 0.0498 mol

5 0

3 years ago