Answer:
a. True
Explanation:
Hello there!
In this case, since the dose-response method is crucial concept in toxicology as it exhibits the result of exposures to toxic chemical compounds with changes in body functions or health, this statement is a. True , as this analysis is understood by means of the relationship -the higher the dose, the more severe the response-, and of course, it is based on observed data from controlled experiments in animal, human clinical, or cell studies, in the light of the determination of the toxicity of the analyzed chemical.
Regards!
True or false, rewrite it to make it true.
To balance a chemical equation, only the subscripts of a reactant and product can be changes
Answer:
false
Explanation:
How many grams of NaOH (MW = 40.0) are there in 500.0 mL
of a 0.175 M NaOH solution?
A) 3.50
B) 114
C) 14.0
D) 2.19x10
Answer:
3.5
Explanation:
500*0.175= 8.75 *40/1000=3500/1000=3.5
Answer:
3.50 grams
Explanation:
Mastering chem
Helpppp me pleaseeee now I’ve been struggling so bad w this
Answer:
I don't know what the passage says, but I feel like the most logical conclusion is D or the last one.
Explanation:
Answer:
D! Hope this helps! Figured id help with all of ur questions!
Explanation:
Im a wiz at science! ;)
Please please help me
Answer:
I agree with Omar because it depends on what the charge of the object and magnet is. If the magnet is negative and the object is positive, they will pull together. If the magnet is negative and the object is negative then they will pull apart.
Explanation:
What is the percent yield of LiCl if I produced 30.85g LiCl and my theoretical yield was calculated to be 35.40g LiCl?
Answer:
87.15%
Explanation:
To find percent yield, we can use this simple equation
[tex]\frac{Actual}{Theoretical} *100[/tex]
Where "Actual" is the amount in grams actually collected from the reaction, and "Theoretical" is, well, the theoretical amount that should have been produced.
They give us these values, so to find the percent yield, just plug the numbers in.
[tex]\frac{30.85}{35.40} *100\\\\ =87.15[/tex]
So, the percent yield is 87.15%
An easy trick to remember how to do this is just to divide the smaller number by the bigger number and move the decimal back two places. If you have a percent yield greater than 100%, something is wrong in the reaction.
A student was directed to convert the mass of a boulder from kg to pounds.
Conversion factor: 1 pound = 454 g
The mass is 22 kg. The student calculated the weight to be 0.048 pounds.
Is this correct? If not, what went wrong?
Answer:
Incorrect
Explanation:
Given that,
The mass of a boulder, m = 22 kg
We need to find the weight of the student in pounds.
We know that,
1 pound = 454 g
or
1 g = (1/454 pounds)
22 kg = 0.022 grams
So,
0.022 grams = [tex]\dfrac{0.022}{454}\ pounds[/tex]
= 0.000048 pounds
The student says the weight is 0.048 pounds. It means he was incorrect.
Match each object to its definition.
A. meteorite
B. meteoroid
C. meteor
->
1. The remains of a rock from space that strikes Earth’s surface
2. A rock that burns up in Earth’s atmosphere
3. A small piece of rock in space
Answer:
definition 1. goes with B. meteoroid
definition 2. goes with C. meteor
definition 3. goes with A. meteorite
Answer: meteoroid - a small piece of rock in space, meteor - a rock that burns up in Earths atmosphere, meteorite - The remains of a rock from space that strike Earth's surface.
Explanation:
Part A
Choose the paramagnetic species from below.
O He
O Te
O T14+
O All of the above are paramagnetic.
None of the above is paramagnetic.
Answer:
o He
Explanation:
basyshsiz0qnshshhsjzz
water
air
multiple cells
a place to live
Answer:
I guess it WATER
How many moles of Ag can be obtained from 2.77 moles Cu using the following
balanced reaction?
2AgNO3
+ Cu
Cu(NO3)2
+ 2Ag
Answer:
2.77×2= 5.4 mol Ag can be obtained
What is the pressure (in atm) in a 5.00 L tank with 9.00 grams of oxygen gas at 350 K?
Answer:
1.61 atm
Explanation:
Using general gas law equation as follows:
PV = nRT
Where;
P = pressure (atm)
V = volume (L)
n = number of moles (mol)
R = gas law constant (0.0821 Latm/molK)
T = temperature (K)
From the information provided in this question,
V = 5.00L
T = 350K
mass of O2 = 9.00g
Using mole = mass/molar mass
Molar mass of O2 = 16(2) = 32g/mol
mole = 9/32
mole = 0.28mol
Using PV = nRT
P = nRT/V
P = 0.28 × 0.0821 × 350/5
P = 8.0458/5
P = 1.609
Pressure = 1.61 atm
The pressure of the oxygen gas at the given temperature and volume is 1.61 atm.
The given parameters;
volume of the gas, V = 5 Lmass of the oxygen gas, m = 9 gtemperature of the gas, T = 350 KThe number of the moles of the given gas is calculated as follows;
[tex]moles = \frac{m}{M} \\\\moles = \frac{9}{32} \\\\moles = 0.28 \ mol[/tex]
The pressure of the gas is calculated as follows;
[tex]PV = nRT\\\\P = \frac{nRT}{V} \\\\P = \frac{0.28 \times 0.0821 \times 350}{5} \\\\P = 1.61 \ atm[/tex]
Thus, the pressure of the oxygen gas at the given temperature and volume is 1.61 atm.
Learn more here:https://brainly.com/question/21912477
Photosynthesis in a plant is an example of which characteristic of living things?
1. Reproduction
2. Response to the environment
3. Growth and development
4. Ability to obtain and use energy
Answer:
4. Ability to obtain and use energyConsider the Fischer ester synthesis of methyl benzoate from benzoic acid and methanol in the presence of sulfuric acid as a catalyst. A reaction was performed in which 3.8 g of benzoic acid was reacted with excess methanol to make 2.0 g of methyl benzoate. Calculate the theoretical yield and percent yield for this reaction.
Answer:
48.8%
Explanation:
The reaction has a 1:1 mole ratio so;
Number of moles of benzoic acid reacted = mass/molar mass = 3.8 g/122.12 g/mol = 0.03 moles
So;
0.03 moles of methyl benzoate is formed in the reaction
Mass of methyl benzoate formed = 0.03 moles * 136.15 g/mol = 4.1 g
percent yield = actual yield/theoretical yield * 100/1
percent yield = 2.0 g/4.1 g * 100 = 48.8%
What is the name of PbS2
Answer:
Lead sulfide.
Explanation:
does anyone know the answer to this
How many moles are there in 8.0 grams of CaCO3
Answer: moles = 0.0799305403604264
Explanation:
what is the name of this structure here please and thanks
Answer:
look at the file that the other person sent
how many moles are 20 grams of Helium ?
Answer: The correct answer is 5.00 moles
Explanation:
What is the molarity of ZnCl, that forms when 20.0 g of zinc completely reacts with CuCl2, according to the following reaction? Assume a final
volume of 285 mL
Zn(s) + CuCl2(aq) → ZnCl2(aq) + Cu(s)
It’s worth 50 points! Please help!
Answer:
1) NO2
2) 49.4%
Explanation:
Which affects both deep water and surface currents in the ocean? the wind the temperature of the water the Coriolis effect None of the above
Answer:
the wind and the temperature of water both drive ocean currents
Answer:
B. Write 'T' for true or 'F' for false statements :
1. Publisher works only with document in fixed shapes and sizes.
2. Viewing tools are only for editing purpose.
3. Text box icon is found in Styles group.
4. Publisher does not allow you to add images to your document.
5. Margin guides are blue lines that mark the edges.
Consider this chemical equation:
2AgNO3(aq) + Cu(s) → Cu(NO3)2(aq) + 2Ag(s)
Which substances dissolve in solution? Select all
that apply.
AgNO3
Cu
Cu(NO3)2
Ag
Answer is:AgNO3 and Cu(NO3)2
Answer:
the answer is very correct as AgNO3 and Cu(NO3)2
Answer:
A,C
Explanation:
the person above me is correct
What part of the food. chain is a pine?
a:primary consumer
b:secondary consumer
c:herbivore
d:producer
Answer:
producer
Explanation:
Help me I’m struggling with this one
Answer:
Eukarya
Explanation:
It's larger than a prokaryotic cell and it has a nucleus.
igneous sedimentary, and metamorphic rocks are found at the same cliff side.Which statement is correct?
Answer:
The metamorphic rock and sedimentary rock were already at this location and magma flowed into other rocks
Explanation:
Which simple machine is best used to split apart an object
A. A screw
B. A lever
C. A wedge
D. A pulley
Answer:
its A screw :))) your welcome
how many moles are in 83 particles of sodium chloride?
Answer:
there are 1.4201927800478769 moles in 83 particles of sodium chloride. or 1.42 for short.
Explanation:
The distance that is covered by the wave in one second is called
Answer:
The distance that is covered by the wave in one second is called frequency.
Explanation:
Please help!
Karl-Anthony is trying to plate gold onto his silver ring. He constructs an electrolyte cell using his ring as one of the electrodes. He runs this cell for 90.6 minutes at 213.8 mA. How many moles of electrons were transferred in this process?
Answer:
0.012 mole of electron
Explanation:
From the question given above, the following data were obtained:
Time (t) = 90.6 minutes
Current (I) = 213.8 mA
Number of mole of electrons =?
Next, we shall convert 90.6 mins to seconds. This can be obtained as follow:
1 min = 60 s
Therefore,
90.6 mins = 90.6 × 60
90.6 mins = 5436 s
Next, we shall convert 213.8 mA to A. This can be obtained as follow:
1000 mA = 1 A
Therefore,
213.8 mA = 213.8 mA × 1 A / 1000 mA
213.8 mA = 0.2138 A
Next, we shall determine the quantity of electricity used in the process. This can be obtained as follow:
Time (t) = 5436 s
Current (I) = 0.2138 A
Quantity of electricity (Q) =?
Q = it
Q = 0.2138 × 5436
Q = 1162.2168 C
Next, the equation for the reaction.
Au⁺ + e —> Au
From the balanced equation above,
1 mole of electron was transferred.
Recall:
1 faraday = 96500 C = 1 e
Thus,
96500 C of electricity is needed to transfer 1 mole of electron.
Finally, we shall determine the number of mole electrons transferred by the application of 1162.2168 C of electricity. This can be obtained as follow:
96500 C of electricity is needed to transfer 1 mole of electron.
Therefore,
1162.2168 C of electricity will transfer = 1162.2168 / 96500 = 0.012 mole of electron
Thus, 0.012 mole of electron was transferred in the process.
Following are the calculation to the moles of electrons that transferred in the process:
Given
Current flows
time[tex]= 90.6\ min = 90.6 \times 60\ sec= 5436 \ sec\\\\[/tex]
For Step 1:
Calculating the Total charge flown in the given time:
For Step 2:
Charge on a single electron
So:
Following are the calculation to the charges of electrons:
Following are the calculation to the electrons transferred:
[tex]=\frac{(726.38\times 10^{19})}{ (6.023 \times 10^{23})}\\\\= 120.60\times 10^{-4}\ moles\\\\[/tex]
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HELP!
The law of conservation of energy states:
A. Energy increases exponentially with times
B. Total energy decreases due to energy output.
C. Energy cannot be created or destroyed.
D. Energy always remains in the same form.
Answer:
C
Explanation:
energy cannot be created or destroyed like solar energy for instance. it is already energy because it comes from the sun and for other reason.
Hope this helps!