What is the right answer for this. I really need help

Science helPPPPPPPPP MEEEEEEEEE RIGHT NOW

Alika [10]

Its is b because that is how the galaxy works.

7 0

2 years ago

Considering 0.10 m solutions of each substance, which contains the smallest concentration of ions

mihalych1998 [28]

Question options:

A) K2SO4

B) FeCl₃

C) NaOH

D) NH₃

E) KCl

Answer:

D. NH₃

Explanation:

K2SO4 = 2 K+ + SO42-

[K+]= 2 x 1.0 = 2.0 M ; [SO42-] = 1.0 M

total concentrations of ions = 2.0 + 1.0 = 3.0 M

FeCl3 = Fe3+ + 3Cl-

[Fe3+] = 1.0 M ; [Cl-] = 3 x 1.0 = 3.0

total concentration ions = 1.0 + 3.0 = 4.0 M

NaOH = Na+ + OH-

[Na+] = [OH-] = 1.0 M

total concentration ions = 1.0 + 1.0 = 2.0 M

NH3 is a weak acid so the concentration of NH4+ and OH- < 2.0

KCl = K+ + Cl-

[K+] = [Cl-] = 1.0 M

total concentration ions = 1.0 + 1.0 = 2.0 M

7 0

3 years ago

Which type of energy would most likely create the worst environmental disaster from an accident or spill?

rewona [7]

Answer:

nuclear energy

Explanation:

6 0

3 years ago

Draw a Lewis structure for C2H3Cl . Include all hydrogen atoms and show all unshared electron pairs. None of the atoms bears a f

Korvikt [17]

Answer:

See attached picture.

Explanation:

Hello!

In this case, since C2H3Cl is an organic compound we need a central C-C parent chain to which the three hydrogen atoms and one chlorine atom provides the electrons to get all the octets except for H as given on the statement.

In such a way, on the attached picture you can find the required Lewis dot structure without formal charges and with all the unshared electron pairs, considering there is a double bond binding the central carbon atoms in order to compete their octets.

Best regards!

5 0

3 years ago

Hello, everyone!

marusya05 [52]

Answer: 27.09 ppm and 0.003 %.

First, for air pollutants, ppm refers to parts of steam or gas per million parts of contaminated air, which can be expressed as cm³ / m³. Therefore, we must find the volume of CO that represents 35 mg of this gas at a temperature of -30 ° C and a pressure of 0.92 atm.

Note: we consider 35 mg since this is the acceptable hourly average concentration of CO per cubic meter m³ of contaminated air established in the "National Ambient Air Quality Objectives". The volume of these 35 mg of gas will change according to the atmospheric conditions in which they are.

So, according to the law of ideal gases,

PV = nRT

where P, V, n and T are the pressure, volume, moles and temperature of the gas in question while R is the constant gas (0.082057 atm L / mol K)

The moles of CO will be,

n = 35 mg x $\frac{1 g}{1000 mg}$ x $\frac{1 mol}{28.01 g}$

→ n = 0.00125 mol

We clear V from the equation and substitute P = 0.92 atm and

T = -30 ° C + 273.15 K = 243.15 K

V = $\frac{0.00125 mol x 0.082057 \frac{atm L}{mol K} x 243 K}{0.92 atm}$

→ V = 0.0271 L

As 1000 cm³ = 1 L then,

V = 0.0271 L x $\frac{1000 cm^{3} }{1 L}$ = 27.09 cm³

Then the acceptable concentration c of CO in ppm is,

c = 27 cm³ / m³ = 27 ppm

To express this concentration in percent by volume we must consider that 1 000 000 cm³ = 1 m³ to convert 27.09 cm³ in m³ and multiply the result by 100%:

c = 27.09 $\frac{cm^{3} }{m^{3} }$ x $\frac{1 m^{3} }{1 000 000 cm^{3} }$ x 100%

c = 0.003 %

So, the acceptable concentration of CO if the temperature is -30 °C and pressure is 0.92 atm in ppm and as a percent by volume is 27.09 ppm and 0.003 %.

5 0

3 years ago