According to embryology, which three species have the closest common ancestor?

Can I please Get Help with This Question ‍♂️?

Stolb23 [73]

Answer:

621.41 grams

Explanation:

First of all, to find the mass. You have to use the molar mass of AlBr3 to convert from moles to mass.

Second of all, find the molar mass of AlBr3.

Al = 27.0 amu

Br = 79.9 amu

They are 3 bromine atoms and 1 aluminum atom.

So you do this

27.0 + 79.9(3) = 266.7

The molar mass is 266.7 g/mol

Third of all, use dimensional analysis to show your work.

2.33 moles of AlBr3 * 266.7 g/mol / 1 mol

Moles cancel out.

2.33 x 266.7 = 621.411

Your teacher though said to round digits after the decimal point instead of using sig figs.

621.411 rounds to 621.41

So the final answer is 621.41 grams(don't forger the units).

The substance formula is just AlBr3.

That's all.

Hope it helped!

8 0

3 years ago

Question 2(Multiple Choice Worth 5 points) (06.04 HC) During a laboratory experiment, 36.12 grams of Al2O3 was formed when O2 re

sladkih [1.3K]

Answer:

8.70 liters.

Explanation:

The balanced equation for the mentioned reaction is:

3O₂ + 4Al → 2Al₂O₃,

It is clear that 3.0 moles of O₂ react with 4.0 moles of Al to produce 2.0 Al₂O₃.

Firstly, we need to calculate the no. of moles (n) of 36.12 g of Al₂O₃:

n = mass/molar mass = (36.12 g)/(101.96 g/mol) = 0.3543 mol.

using cross multiplication:

3.0 mol of O₂ produces → 2.0 mol of Al₂O₃.

??? mol of O₂ produces → 0.3543 mol of Al₂O₃.

∴ The no. of moles of O₂ needed to produce 36.12 grams of Al₂O₃ = (3.0 mol)(0.3543 mol)/(2.0 mol) = 0.5314 mol.

Now, we can find the volume of O₂ used during the experiment:

We can use the general law of ideal gas: PV = nRT.

where, P is the pressure of the gas in atm (P = 1.4 atm).

V is the volume of the gas in L (V = ??? L).

n is the no. of moles of the gas in mol (n = 0.5314 mol).

R is the general gas constant (R = 0.0821 L.atm/mol.K),

T is the temperature of the gas in K (T = 280 K).

∴ V = nRT/P = (0.5314 mol)(0.0821 L.atm/mol.K)(280 K)/(1.4 atm) = 8.726 L ≅ 8.70 L.

So, the right choice is: 8.70 liters.

5 0

3 years ago

Read 2 more answers

A chlorine Cl and bromine Br atom are adsorbed on a small patch of surface (see sketch at right). This patch is known to contain

MrRissso [65]

Explanation:

It is given that possible number of ways the Cl and Br can be absorbed initially are 100.

S, possible number of ways by which Br can be desorbed is as follows.

$100 \times 99$

Now, we will calculate the change in entropy as follows.

$\Delta S = k_{B} ln (\frac{W}{W_{o}})$

where, $k_{B}$ = Boltzmann constant = $1.38 \times 10^{-23}$

$\Delta S$ = change in entropy

Therefore, we will calculate the change in entropy as follows.

$\Delta S = k_{B} ln (\frac{W}{W_{o}})$

= $1.38 \times 10^{-23} J/K \times ln (\frac{100}{100 \times 99})$

= $1.38 \times 10^{-23} J/K \times -4.595$

= $-6.34 \times 10^{-23} J/K$

Thus, we can conclude that the change in entropy is $-6.34 \times 10^{-23} J/K$ .

5 0

3 years ago

What kind of geometry does the following molecule have? CF4

elixir [45]

What kind of geometry does the following molecule have? CF4 - Tetrahedral

5 0

4 years ago

NH4Cl and Na3PO4 Balanced Equation Total Ionic Equation Net Ionic Equation

kondor19780726 [428]

Answer:

No Reaction => Does not react to form a Driving Force compound

Explanation:

6 0

3 years ago