Arrange these elements in order of decreasing atomic size:sulfur, chlorine, aluminium, and sodium.

What is the highest energy to which doubly ionized helium atoms (alpha particles) can be accelerated in a DC accelerator with 3

pentagon [3]

Answer:

Highest energy will be equal to $9.6\times 10^{-13}J$

Explanation:

Charged on doubly ionized helium atom $q=2e=2\times 1.6\times 10^{-19}C=3.2\times 10^{-19}C$

It is accelerated with maximum voltage of 3 MV

So voltage $V=3\times 10^6volt$

Now energy is given by $E=qV=3.2\times 10^{-19}\times 3\times 10^6=9.6\times 10^{-13}J$

So highest energy will be equal to $9.6\times 10^{-13}J$

5 0

3 years ago

Estradiol is a female sexual hormone that causes maturation and maintenance of the female reproductive system. Elemental analysi

Ipatiy [6.2K]

Answer:

The molecular formula of estradiol is: $C_{18}H_{24}O_2$ .

Explanation:

Molar mass of of estradiol = M= 272.37 g/mol

Let the molecular formula of estradiol be $C_xH_yO_z$

Percentage of an element in a compound:

$\frac{\text{Number of atoms of element}\times \text{Atomic mass of element}}{\text{molecular mass of element}}\times 100$

Percentage of carbon in estradiol :

$\frac{x\times 12 g/mol}{272.37 g/mol}\times 100=79.37\%$

x = 18.0

Percentage of hydrogen in estradiol :

$\frac{y\times 1g/mol}{272.37 g/mol}\times 100=8.88\%$

y = 24.2 ≈ 24

Percentage of oxygen in estradiol :

$\frac{z\times 16 g/mol}{272.37 g/mol}\times 100=11.75\%$

z = 2

The molecular formula of estradiol is: $C_xH_yO_z:C_{18}H_{24}O_2$

7 0

3 years ago

A catalyst

kotegsom [21]

A catalyst speeds up the rate of reaction so the answer is B.

8 0

3 years ago

Use the molar bond enthalpy data in the table to estimate the value of Δ∘rxn

MakcuM [25]

Answer:

ΔH°rxn = - 433.1 KJ/mol

Explanation:

CH4(g) + 4Cl2(g) → CCl4(g) + 4HCl(g)

⇒ ΔH°rxn = 4ΔH°HCl(g) + ΔH°CCl4(g) - 4ΔH°Cl2(g) - ΔH°CH4(g)

∴ ΔH°Cl2(g) = 0 KJ/mol.....pure element in its reference state

∴ ΔH°CCl4(g) = - 138.7 KJ/mol

∴ ΔH°HCl(g) = - 92.3 KJ/mol

∴ ΔH°CH4(g) = - 74.8 KJ/mol

⇒ ΔH°rxn = 4(- 92.3 KJ/mol) + (- 138.7 KJ/mol) - 4(0 KJ/mol) - (- 74.8 KJ/mol)

⇒ ΔH°rxn = - 369.2 KJ/mol - 138.7 KJ/mol - 0 KJ/mol + 74.8 KJ/mol

⇒ ΔH°rxn = - 433.1 KJ/mol

4 0

3 years ago

Read 2 more answers

β‑Galactosidase (β‑gal) is a hydrolase enzyme that catalyzes the hydrolysis of β‑galactosides into monosaccharides. A 0.387 g sa

gtnhenbr [62]

Answer:

The molar mass of unknown β‑Galactosidaseis 116,352.97 g/mol.

Explanation:

To calculate the concentration of solute, we use the equation for osmotic pressure, which is:

$\pi=icRT$

where,

$\pi$ = osmotic pressure of the solution = 0.602 mbar = 0.000602 bar

0.000602 bar = 0.000594 atm

(1 atm = 1.01325 bar)

i = Van't hoff factor = 1 (for non-electrolytes)

c = concentration of solute = ?

R = Gas constant = $0.0820\text{ L atm }mol^{-1}K^{-1}$

T = temperature of the solution = $25^oC=[273.15 +25]=298.15 K$

Putting values in above equation, we get:

$0.000594 atm=1\times c\times 0.0821\text{ L.atm }mol^{-1}K^{-1}\times 298.15 K\\\\c=2.4278\times 10^{-5} mol/L$

The concentration of solute is $2.4278\times 10^{-5} mol/L$

Volume of the solution = V =0.137 L

Moles of β‑Galactosidase = n

$C=\frac{n}{V(L)}$

$n=2.4278\times 10^{-5} mol/L\times 0.137 L$

$n=3.3261\times 10^{-6} mol$

To calculate the molecular mass of solute, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Moles of β‑Galactosidase = $3.3261\times 10^{-6} mol$

Given mass of β‑Galactosidase= 0.387 g

Putting values in above equation, we get:

$3.3261\times 10^{-6} mol =\frac{0.387 g}{\text{Molar mass of solute}}\\\\\text{Molar mass of solute}=116,352.97 g/mol$

Hence, the molar mass of unknown β‑Galactosidaseis 116,352.97 g/mol.

3 0

3 years ago

Arrange these elements in order of decreasing atomic size:sulfur, chlorine, aluminium, and sodium.​

Arrange these elements in order of decreasing atomic size:sulfur, chlorine, aluminium, and sodium.