Answer:
A. the cathode
Explanation:
Answer:
A. The cathode
Explanation:
a p e x
The following is a list of common errors encountered in research laboratories. Categorize each as a determinate or an indeterminate error, and further categorize determinate errors as instrumental, operative, or methodic:
(a) An unknown being weighed is hygroscopic.
(b) One component of a mixture being analyzed quantitatively by gas chromatography reacts with the column packing.
(c) The tip of the pipet used in the analysis is broken.
(d) In measuring the same peak heights of a chromatogram, two technicians each report different heights.
Answer:
An unknown being weighed is hygroscopic. - operative error
One component of a mixture being analyzed quantitatively by gas chromatography reacts with the column packing. - methodic error
The tip of the pipet used in the analysis is broken. - instrumental error
In measuring the same peak heights of a chromatogram, two technicians each report different heights - operative error
Explanation:
In chemical analysis, operative errors are that largely introduced into the measurement because of variation of personal judgements of analysts. It is also a personal error that emanates solely due to the analyst.
A methodic error arises as a result of adopting defective experimental methods. For example, a column packing that reacts with a component of the mixture is used in the gas chromatography.
Instrument error refers to the error of a measuring instrument, for instance, the use of a pipette with a broken tip.
What is the mean of the data set [3, 2, 2, 12, 6, 5, 14,4)?
O2
O 7
Answer:
the mean is 6 but you don't have that as an option.
Explanation:
the mean is the average.
to find the mean you have to add all of your data first
3 + 2 + 2 + 12 + 6 + 5 + 14 + 4 = 48
then you have to divide your answer by how many numbers there are in total.
48 / 8 = 6
the mean is 6.
Convert 3.4 moles of sodium oxalate into grams. Show all your work .
Answer:
m = 455,6 g
Explanation:
The mass can be determined by calculating the amount of substance times the molar mass:
m = n * M
To do this, you first have to calculate the molar mass of sodium oxalate. It is made up of the molar masses of the individual atoms. The molecular formula of sodium oxalate is:
[tex]Na_{2}C_{2}O_{4}[/tex]
M(Na) = 23 g/mol; M(C) = 12 g/mol; M(O) = 16 g/mol
M(Na2C2O4) = 2 * M(Na) + 2 * M(C) + 4 * M(O)
M(Na2C2O4) = 2 * 23 g/mol + 2 * 12 g/mol + 4 * 16 g/mol
M(Na2C2O4) = 134 g/mol
m = n * M
m = 3,4 mol * 134 g/mol
m = 455,6 g
In a mixture of bromine-79 and bromine-81 isotopes. An atom of bromine-79 contains?
Answer:
Bromin-79
Explanation:
The isotope bromine-79 will contain 35 protons, 35 electrons and 44 neutrons.
Help me this, I only have 10 minutes to answer!!!!
Answer:sedimentary
Explanation:
How are contact forces and non-contact forces similar?
Answer:
Difference between Contact and Non-Contact Forces
There is no field linked with the contact force. There is always a field linked with non-contact force. The frictional force is an example of a contact force. Gravitational force is an example of a non-contact force.
Explanation:
And it is physics not chem.
Hope this helps u
Crown me as brainliest:)
What is the toto number of neutrons in an atom of 73 li
Acetylsalicylic acid (C9H8O4) is a monoprotic acid commonly known as aspirin. A typical aspirin tablet, however, contains only a small amount of the acid. In an experiment to determine its composition, an aspirin tablet was crushed and dissolved in water. It took 14.40 mL of 0.1466 M NaOH to neutralize the solution. Calculate the number of grains of aspirin in the tablet. (One grain = 0.0648 g and the molar mass of aspirin = 180.2 g/mol.)
Answer:
6 grains
Explanation:
The equation of the reaction between NaOH and aspirin is;
C9H8O4(aq) + NaOH (aq) ------>C9H7O4Na(aq) + H2O(l)
Amount of NaOH reacted = concentration × volume = 0.1466 M × 14.40/1000 L = 2.11 × 10^-3 moles
Given that aspirin and NaOH react in a mole ratio of 1:1 from the balanced reaction equation above, the number of moles of aspirin reacted is 2.11 × 10^-3 moles
Hence mass of aspirin reacted = 2.11 × 10^-3 moles × 180.2 g/mol = 0.38 g
If 1 grain = 0.0648 g
x grains = 0.38 g
x= 0.38 g/0.0648 g
x= 6 grains
Right amount of gravity
the answer is: 9.80665
How many grams of Al are needed to react with 91.8 grams of FeO
3FeO + 2Al —> 3 Fe +Al2O3
Answer:
Ans : 22.86 gm of Aluminium
Solution,
3FeO + 2Al ---> 3 Fe + [tex]Al_{2}O_{3}[/tex]
Given 3 2
Find 1.27 x
By the given gms of FeO find its mole and put the moles in the find,
[tex]n = \frac{given mass}{molecular mass}[/tex]
Given mass of FeO is 91.8
Molecular mass of FeO is 71.8
n = [tex]\frac{91.8}{71.8}[/tex]
n = 1.27 moles of FeO
Now solve for x,
[tex]x = \frac{2 x 1.27}{71.8}[/tex]
x = 0.85 moles
These are just moles of Aluminium that we need to react with FeO, so to find Grams of Aluminium we need,
Mass = moles x molecular mass
Mass = 0.85 x 27(atomic mass of Al)
Mass = 22.86 grams of aluminium is what we need
Please helpppp!!!!!! It's 6th-grade thermal energy science.
Answer:
b?
Explanation:
The answer is C: Radiant energy from the sun travels through the glass, is absorbed by the black pot, and reflected by the aluminum foil.
The process by which vesicles move substances out of a cell is
Calcium reacts with oxygen to make calcium oxide, CaO. What is the theoretical yield (g) of CaO(s) that could be prepared from 7.75 g of Ca(s) and 2.44 g of O2(g)
Answer:
Explanation:
2Ca + O₂ = 2CaO
80 g 32 g 112 g
given amount of Ca = 7.75 g
it will require oxygen = 32 x 7.75 / 80 = 3.1 g
but available oxygen = 2.44 so oxygen is the limiting reagent .
32g oxygen reacts with calcium to give 112 g of calcium oxide
2.44 gram of oxygen reacts with calcium to give 112 x 2.44 / 32 of CaO .
= 8.54 gram .
Theoretical yield of CaO = 8.54 gram.
which statement describes how technology has increased our information on Mars?
A. The Curiosity rover found sulfur compound in rocks.
B.The Curiosity rover located methane in soil samples.
C. The Curiosity rover detected carbon in organic molecules.
D. The Curiosity rover discovered helium in underground pockets.
Answer:
Either D or C. I'm so sorry if I got you the wrong answer
Answer:
c
Explanation:
How many elements are in H2CrO4
Answer:
3 elements
Explanation:
The elements are:
- Chromium
- Hydrogen
- Oxygen
Which elements is the most reactive on this table?
Answer:
alkali metals
Explanation:
alkali metals only have one valence electron, meaning they are extremely reactive. they are considered the most reactive on the periodic table.
A piece of metal is composed of atoms. Each atom in the metal contains 29 protons. How is the metal classified?
Answer:
The metal is Copper
Explanation:
Matter is composed of atoms, which is the smallest indivisible particle of an element. The atom of an element consists of three subatomic particles namely: proton, electron and neutron etc.
The proton, which is the positively charged particle, is equal to the electron, which is the negatively charged particle. The proton number of the atom is the ATOMIC NUMBER of an element.
In the periodic table, the element with atomic number 29, which also means proton number 29 is Copper (Cu).
What is the name for the type of graph shown in the image below?
Box-and-whisker
Histogram
Line
Scatter plot
Answer:
Scatter plot
Explanation:
Because the plot is scattered all over the place
Which part of a flower can make eggs
Answer:Within the flower, sperm cells are produced by pollen at the tips of stamens, while egg cells develop in ovules, tiny structures embedded in the ovary at the base of the pistil.
I didn't realize the person up top had the same answer give them the brainliest! :)
The mass of 1 gram:
is kept as a standard platinum cylinder in France
equals 1 cm³
is .01 kg
equals the mass of 1 mL of water at 4°C
Answer:
C. equals the mass of 1 mL of water at 4°C
Explanation:
Pure H2oboils at 100 ˚C and freezes at 0 ˚C. What is the melting point and boiling point of water
after the addition of potassium chloride
Answer:
Recall the colligative properties of freezing point depression and boiling point elevation.
In proportion to the molality product of the solute, (
i
m
), the boiling point will raise and the freezing point will decrease.
Now, consider tap water. You know this!
Is tap water pure water? Of course not! It's a solution of many ions of metals or other inorganic compounds.
Hence, it has a varied boiling and melting point, by definition.
Explanation:
The colligative properties like the boiling point elevation and freezing point depression depend on the solute concentration. The boiling point of the water will increase while the freezing point will decrease.
What are colligative properties?Colligative properties are the attributes that depend on the amount or the solute concentration rather than on the type or identity of the solute particle. They include freezing point depression, lowering of vapor pressure, osmotic pressure, and boiling point elevation.
The boiling point elevation is the increase of the solvent's boiling point by the addition of the solute. Potassium chloride is a salt and a non-volatile solute that increases the boiling point of the solution.
The freezing point depression is one of the colligative properties that states the direct relationship between the molality and the freezing point of the solvent. As potassium chloride is a non-volatile solute it decreases the freezing point of the substance.
Therefore, the boiling point will increase but the freezing point will decrease after the addition of potassium chloride.
Learn more about colligative properties here:
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The specific heat of silver is 0.24 J/g•°C. How many joules of energy are needed to warm 4.37 g of silver from 25.0°C to 27.5°C?
A. 2.6 J
B. 46 J
C. 0.14 J
D. 0.022 J
The heat energy needed to change the temperature of 4.37 gram of silver sample of specific heat 0.24 J/ g °C from a temperature of 25 to 27.5 °C is 2.6 J.
What is calorimetry ?Calorimetry is an analytical technique used to determine the heat energy absorbed or released by a system. The calorimetric equation relating the heat energy q with the mass of the substance m, specific heat c and temperature difference ΔT is given as:
q = m c ΔT.
Given that the mass of the sample of iron = 20 g
temperature difference ΔT = 27.5 - 25 = 2.5 °C
specific heat c = 0.24J/ g °C.
The heat energy absorbed by the sample is calculated as follows:
q = 4.37 g × 0.24 J/ g °C × 2.5 °C
= 2.6 J.
Therefore, the heat energy required to the raise the temperature of the sample of iron is 2.6 J.
Find more on calorimetry :
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Write the equation for the dehydration of the CoCl2 hydrate
i need help please help me now please
Imagine there is technology that allows scientists to see all of the movement of molecules inside living things. A scientist points this machine at the stem of a vascular plant and sees glucose molecules being transported to various parts of the plant. The scientist is looking at the movement of molecules through
the xylem.
the phloem.
the roots.
the cuticle.
Answer: C
Explanation: I looked it up lol
Calculate the density of an
object with a mass of 20 g
and a volume of 2.3 mL.
Answer:
8.7g/mL
Explanation:
I used the density formula to solve. d=m/v= 20g/2.3mL
Answer:
8.7 g/ml
Explanation:
the formula for density is D = M/V
What is the temperature, in degrees Celsius, of a 10.5 grams sample of Neon gas confined to a volume of 2.50 L at a pressure of 1.00 atm.
Answer:
–215 °C
Explanation:
From the question given above, the following data were obtained:
Mass of Ne = 10.5 g
Volume (V) = 2.50 L
Pressure (P) = 1 atm
Temperature (T) =?
Next, we shall determine the number of mole present in 10.5 gof Neon, Ne. This can be obtained as follow:
Mass of Ne = 10.5 g
Molar mass of Ne = 20 g/mol
Mole of Ne =.?
Mole = mass /Molar mass
Mole of Ne = 10.5 / 20
Mole of Ne = 0.525 mole
Next, we shall determine the temperature of the sample of Neon, Ne. This can be obtained as follow:
Volume (V) = 2.50 L
Pressure (P) = 1 atm
Number of mole (n) = 0.525 mole
Gas constant (R) = 0.0821 atm.L/Kmol
Temperature (T) =?
PV = nRT
1 × 2.5 = 0.525 × 0.0821 × T
2.5 = 0.525 × 0.0821 × T
Divide both side by 0.525 × 0.0821
T = 2.5 / (0.525 × 0.0821)
T = 58 K
Finally, we shall convert 58 K to degree celsius (°C). This can be obtained as follow:
T(°C) = T(K) – 273
T(K) = 58 K
T(°C) = 58 – 273
T(°C) = –215 °C
Thus, the temperature of the sample of Neon gas is –215 °C.
The force of 20 N acts upon a 5kg block. What is the acceleration of the block?
100 m/s/s
4 m/s/s
O 25 m/s/s
O 0.25 m/s/s
Answer:
The answer is 4 m/s²Explanation:
The acceleration of an object given it's mass and the force acting on it can be found by using the formula
[tex]a = \frac{f}{m} \\ [/tex]
where
a is the acceleration
f is the force
m is the mass
From the question
f = 20 N
m = 5 kg
We have
[tex]a = \frac{20}{5} \\ [/tex]
We have the final answer as
4 m/s²Hope this helps you
If the reaction yield is 88.2%,what mass in grams of hydrogen is produced by the reaction of 7.73 g of magnesium with 1.31 g of water
Mg + 2h2o >>mg(oh)2+h2
Answer:
Mass of hydrogen produced is 0.07g.
Explanation:
Given data:
Mass of magnesium = 7.73 g
Mass of water = 1.31 g
Reaction yield = 88.2%
Mass of hydrogen produced = ?
Solution:
Chemical equation:
Mg + 2H₂O → Mg(OH)₂ + H₂
Number of moles of water:
Number of moles = mass/ molar mass
Number of moles = 1.31 g / 18 g/mol
Number of moles = 0.07 mol
Number of moles of magnesium:
Number of moles = mass/ molar mass
Number of moles = 7.73 g / 18 g/mol
Number of moles = 0.43 mol
Now we will compare the moles of water and magnesium with hydrogen.
Mg : H₂
1 : 1
0.43 : 0.43
H₂O : H₂
2 : 1
0.07 : 1/2×0.07 = 0.035
Mass of hydrogen:
Mass = number of moles × molar mass
Mass = 0.035 mol × 2 g/mol
Mass = 0.07 g
Answer: 0.064 grams is the answer
Explanation:
at the end you must multiply 88.2/100*0.073=0.064
Water is composed of one atom of oxygen and two atoms of
Answer:
Hydrogen.
Explanation:
You've probably seen "[tex]H_{2}0[/tex]" which is the formula for water. It means that there's 2 hydrogen atoms, and one oxygen atom, in one molecule of water.
Hope this helps! Feel free to mark me Brainliest if you feel this helped. :)
Answer:
the answer is H. (hydrogen)