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4 years ago

Antibiotics do not reduce the number of helpful and harmful bacteria in the microbiome.

Chemistry

2 answers:

stira [4]4 years ago

7 0

Answer:

false; the purpose of antibiotics is to kill bacteria

Explanation:

mel-nik [20]4 years ago

4 0

It is true, it does reduce the number in both categories.

You might be interested in

a student needs to use 0.575 moles of sodium chloride in an experiment. How many grams should he mass out?

Bad White [126]

The molecular weight of NaCl is 58.44 g/mol.

0.575 mol * 58.44 g/mol = 33.6 grams of NaCl

5 0

3 years ago

A 40.0-L sample of fluorine is heated from 90.0°C to 186.0°C. What volume will the sample occupy at the higher temperature?

jasenka [17]

Answer:

The volume will be 82.67 L

Explanation:

Charles's Law is the relationship between the volume and temperature of a certain amount of ideal gas. In this way, Charles's law is a law that says that when the amount of gas and pressure are kept constant, the ratio between volume and temperature will always have the same value:

$\frac{V}{T} = k$

Having a certain volume of gas V1 that is at a temperature T1 at the beginning of the experiment, by varying the volume of gas to a new value V2, then the temperature will change to T2, and it will be true:

$\frac{V1}{T1} =\frac{V2}{T2}$

In this case, you know:

V1= 40 L
T1= 90 °C
V2= ?
T2= 186 °C

Replacing:

$\frac{40L}{90C} =\frac{V2}{186 C}$

Solving:

$V2=\frac{40L}{90C} *186 C$

V2= 82.67 L

<u><em>The volume will be 82.67 L</em></u>

5 0

3 years ago

What is the energy of a photon of violet light with a frequency of 7.57x10^14 s^-1?

Eddi Din [679]

Answer:

ΔE = 5.02 x 10⁻¹⁹ j

Explanation:

ΔE (photon) = h·f = (6.63 x 10⁻³⁴ j·s)(7.57 x 10¹⁴ s⁻¹) = 5.02 x 10⁻¹⁹ j

h = Planck's Constant = 6.63 x 10⁻³⁴ j·s

f = frequency (given) = 7.57 x 10¹⁴ s⁻¹

6 0

3 years ago

A flash distillation chamber operating at 101.3 kpa is separating an ethanol water mixture the feed mixture contains z weight et

Alex73 [517]

Answer:

The answer is $[\frac{LX_1}{46} + \frac{L(1-x)}{18}]\times0.454$ mol/hr

$[\frac{Vy_1}{46}+\frac{V(1-y)}{18}]\times0.454$ mol/hr

Explanation:

For flash distillation

F = V+L

$\frac{V}{F} + \frac{L}{F} = 1$

$\frac{F}{V} -\frac{L}{V} = 1$

Fz = Vy+Lx

Y = $\frac{F}{V}\times Z - \frac{L}{V}\times X$ let, $\frac{V}{F} = F$

$y = \frac{Z}{F} -[ \frac{1}{F} -1]\times X$

Highlighted reading

F = 299; $\frac{V}{F}$ = 0.85 ; z = 0.36

y = $\frac{0.36}{0.85} - (-0.15)\times X$

= 0.423 + 0.15x ------------(i)

$y^{*}$ = -43.99713 $x^{6}$ + 148.27274 $x^{5}$ - 195.46 $x^{4}$ +127.99 $x^{3}$ -43.3 $x^{2}$ + 7.469 $x^{}$ + 0.02011

At equilibrium, $y^{*}$ = y

0.423+0.15 $x^{}$ = $y^{*}$

-43.99713 $x^{6}$ + 148.27274 $x^{5}$ - 195.46 $x^{4}$ +127.99 $x^{3}$ -43.3 $x^{2}$ + 7.319 $x^{}$ -0.403

F(x) for Newton's Law

Let $x_{0} = 0$

$x_{1}$ = $\frac{0-[{-0.403}]}{7.319}$

= 0.055

$x_{2}$ = $\frac{{0.055}-{f(0.055)} {{{{{{{}}}}}}}}{f^{'} (0.055)}$

= $\frac{{(0.055)}-(-0.11)}{3.59}$

= 0.085

$x^{3}$ = $\frac{{0.085}-(0.024)}{2.289}$

= 0.095

$x^{4}$ = $\frac{{0.095}-(-0.0353)}{-1.410}$

= 0.07

From This x and y are found from equation (i) and L and V are obtained from $\frac{V}{F}$ and F values

$[\frac{LX_1}{46} + \frac{L(1-x)}{18}]\times0.454$ mol/hr

$[\frac{Vy_1}{46}+\frac{V(1-y)}{18}]\times0.454$ mol/hr

8 0

3 years ago

If 40.0 g of water at 70.0°c is mixed with 40.0 g of ethanol at 10.0°c, what is the final temperature of the mixture?

FinnZ [79.3K]

When the heat lost by water = heat gained by ethanol

∴( M* C * ΔT )w = (M*C*ΔT ) eth

when Mw mass of water = 40 g

C specific heat of water = 4.18

ΔT = (70- Tf)

and M(eth) mass (ethanol) = 40 g

C specific heat of ethanol = 2.44

ΔT = (Tf - 10 )

by substitution:

40* 4.18 * (70 - Tf) = 40 * 2.44 * (Tf-10)

∴Tf = 47.9 °C

3 0

3 years ago