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2 years ago

4

Would you expect Penicillin G to show a Zone of Inhibition around its disk on a plate inoculated with E. coli ? Explain briefly

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1 answer:

Gennadij [26K]2 years ago

6 0

Hey kiss’s igfdc okbfv

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Vinegar is an aqueous solution of acetic acid, ch3cooh. a 5.00 ml sample of a particular vinegar requires 26.90 ml of 0.175 m na

Fed [463]

The molarity of acetic acid in the vinegar is 0.94 M

<u><em> calculation</em></u>

Step 1: write the balanced equation between CH3COOH + NaOH

that is CH3COOH + NaOH → CH3COONa + H2O

step 2 : find the moles of NaOH

moles =molarity x volume in L

volume in liters = 26.90/1000=0.0269 l

moles = 0.175 mol /L x 0.0269 L =0.0047 moles of NaOH

Step 3: use the mole ratio to find moles of CH3COOH

that is the mole ratio of CH3COOH: NaOH is 1:1 therefore the moles of CH3COOH is =0.0047 moles

Step 4: find the molarity of CH3COOH

molarity = moles/volume in liters

volume in liter = 5.00/1000 =0.005 l

molarity is therefore=0.0047 moles/ 0.005 l = 0.94 M

4 0

2 years ago

When potassium bromate (kbro3 ) is heated, it decomposes into potassium bromide and a gas that supports the combustion of a glow

Tom [10]

We know that the oxygen (O2) causes a glowing splint to reignite, however, let us check what is missing on the products side of the chemical equation: <span>
KBrO3 → KBr + ?
As we see, oxygen (O2) is the element missing from the other side. Therefore the balanced chemical equation for this decomposition is as follows: </span>
<span>2KBrO3 → 2KBr + 3O2 </span>

6 0

2 years ago

Using the idea of electronegativity difference for predicting polarity of bonds and considering the shape of the following molec

Zinaida [17]

See electronegativity is the tendency of an atom to gain an electron and flourine with a valecy of one and a vey small size is the most electronegetive because its orbitals are quite closed to the nucleus and hence the attraction is quite strong so it can attract an electron.the question that arises is that some smaller atoms should be more electronegetive as they are closer to the nucleus but it need more energy for them as compared to flourine to complete their octet. now polarity increases when two atoms of quite different sizes form a compound ... the more electronegetive atom will always attract the bond pair forming a negetive charge on it and positive on the less electroneg. one and polarity increases with electronegetivity of the anion.now as your question says
<span>5=I2.. because both the atoms are same there wont be permanent polarity </span>
<span>4=HI iodine is the least electronegetive of all the halogens due to its large size,electronegetivity decreases down the group </span>
<span>3=HBr bromine is the 2nd largest halogen </span>
<span>2=HCl chlorine is the 3rd largest halogen </span>
<span>1=HF fluorine is the smallest halogen making and hence makes the most polar</span>

8 0

2 years ago

In the manufacture of paper, logs are cut into small chips, which are stirred into an alkaline solution that dissolves several o

Kitty [74]

Answer:

The estimated feed rate of logs is 14.3 logs/min.

Explanation:

The product of the process is 2000 tons/day of dry wood pulp, of 85 wt% of cellulose. That represents (2000*0.85)=1700 tons/day of cellulose.

That cellulose has to be feed by the wood chips, which had 47 wt% of cellulose in its composition. That means you need (1700/0.47)=3617 tons/day of wood chips to provide all that cellulose.

Th entering flow is wood chips with 45 wt% of water. This solution has an specific gravity of 0.640.

To know the specific gravity of the wood chips we have to write a volume balance. We also know that Mw=0.45*M and Mc=0.55*M.

$V=V_c+V_w\\\\M/\rho=M_c/\rho_c+Mw/\rho_w\\\\M/\rho=0.55*M/\rho_c+0.45*M/\rho_w\\\\1/\rho=0.55/\rho_c +0.45/\rho_w\\\\0.55/\rho_c=1/\rho-0.45/\rho_w\\\\0.55/\rho_c=1/(0.64*\rho_w)-0.45/\rho_w=(1/\rho_w)*(\frac{1}{0.64}-\frac{0.45}{1} )\\\\0.55/\rho_c=1.1125/\rho_w\\\\\rho_c=\frac{0.55}{1.1125}*\rho_w= 0.494*\rho_w$

The specific gravity of the wood chips is 0.494.

The average volume of a log is

$V_l=(\pi*D^{2} /4)*L=(3.1416*\frac{8^{2} \, in^{2} }{4} )*9ft*(\frac{12 in}{1ft})= 21714 in^{3}=12.57 ft^{3}$

The weight of one log is

$M=\rho*V=0.494*\rho_w*12.57 ft^{3}\\\\M=0.494*62.4\frac{lbm}{ft^{3} }*12.57ft^{3}\\\\M=387.5lbm$

To provide 3617 ton/day of wood chips, we need

$n=\frac{supply}{M_{log}}=\frac{3617 tons/day}{387.5 lbm}*\frac{2204lbm}{1ton}\\\\n=20573 logs/day=14.3 logs/min$

The feed rate of logs is 14.3 logs/min.

7 0

2 years ago

Read 2 more answers

Give the product for the reaction of 1-butene with methanol in the presence of acid. The mechanism is the same as the mechanism

Nuetrik [128]

Answer:

The final result is <u>2-methoxybutane. </u>

<u />

Explanation:

1-butene has a carbon-carbon double bound between C1 and C2.

When it will react with methanol, in the presence of an acid, the result will be an ether.

C4H8 + CH3OH → C5H12O

An acid-catalyzed ether synthesis from alkenes is limited by carbocation stability.

In the first step, the double bound will disappear. The C2 atom will be a C+ atom, this becaus it has only 3 bounds and not 4.

This C+ -atom will atract the O- atom to form an ether. The CH3 of methanol will bind on the C3 atom, this is the most stable position.

2-methoxybutane will be formed. It has a structural formula of C5H12O

1-methoxybutane will not be formed, because it's less stable.

1-butanol will be formed when water is added to 1-butene. The mechanism has the same principle but not the same product.

1-ethoxybutane and 2-ethoxybutane have a structural formula of C6H14O, this will not be the final result.

The final result is <u>2-methoxybutane. </u>

<u />

8 0

2 years ago