Solution :
The reasons for the melting point determines :
the assignment of the sample's purityidentification of the unknown samplethe conversion of solid sample to the liquid completelyIn order to prepare the sample in the capillary tube for determining its melting point, we tap the tube gently into the sample with the open end of tube down. We then continue tapping the tube till the sample is couple of millimeters high.
Then the other close end of tube down, we tap the sample down again slowly or then dropping the tube into a longer tube so as to move down the sample faster.
If you have 9.56 moles of aluminum oxide how many moles of sodium oxide could you produce?
Answer:
The answer is 28.68 moles
Explanation:
Hope this helped Mark BRAINLEST!!!
The subscript represents the number of ____________ in a chemical equation.
Limiting Reactant
12.0 grams of sodium reacts with 5.00 grams of chlorine. What mass of sodium
chloride could be produced?
Nas) +
Cl2(g) →
NaCls)
(1)
(2)
Identify the limiting reactant.
Determine the amount of sodium chloride produced.
Answer:
(1) Cl₂ is the limiting reactant.
(2) 8.18 g
Explanation:
2Na(s) + Cl₂(g) → 2NaCl(s)First we convert the given masses of reactants into moles, using their respective molar masses:
Na ⇒ 12.0 g ÷ 23 g/mol = 0.522 mol NaCl₂ ⇒ 5.00 g ÷ 70.9 g/mol = 0.070 mol Cl₂0.070 moles of Cl₂ would react completely with (2 * 0.070) 0.14 moles of Na. There are more Na moles than that, so Na is the reactant in excess while Cl₂ is the limiting reactant.
Then we calculate how many moles of NaCl are formed, using the limiting reactant:
0.070 mol Cl₂ * [tex]\frac{2molNaCl}{1molCl_2}[/tex] = 0.14 mol NaClFinally we convert NaCl moles into grams:
0.14 mol NaCl * 58.44 g/mol = 8.18 gUse the solubility rules from the Lab 4 introduction and your knowledge of qualitative separation schemes from the lab to answer the following questions. The qualitative analysis experiment you did is actually an abbreviated version of a much larger analysis scheme in which many different cations are separated and identified. Suppose a mixture contains Ag , K , NH4 , Hg22 , Pb2 , Mg2 , Sr2 , Ba2 , Cu2 , Al3 and Fe3 .
(a) Which of the following ions could you separate, by causing them to precipitate, with the addition of HCl?
Ag+ K+ NH4+
Hg22+ Pb2+ Mg2+
Sr2+ Ba2+ Cu2+
Al3+ Fe3+
(b) After the addition of HCl, the above sample is centrifuged and decanted. Which of the following cations remaining in the supernatant could you separate, by causing them to precipitate, with the addition of H2SO4? (Hint: H2SO4 is a source of sulfate ions. Select all that apply.)
Ag+ K+ NH4+
Hg22+ Pb2+ Mg2+
Sr2+ Ba2+ Cu2+
Al3+ Fe3+
Answer:
a13+a13
Explanation:
How are humidity and precipitation related?
A. When humidity is low, the chance of precipitation is high.
B. When humidity is high, the chance of precipitation is high.
C. When humidity is high, the chance of precipitation is low.
D. Changes in humidity do not cause precipitation.
[Kr]5s24d25p1
Express your answer as a chemical symbol.
Answer:
kr(5)s24d25p1
=5d25kprs24
Which phrase describes air density?
increases as altitude increases
equals mass divided by volume
pushes molecules in one direction
exerts less pressure as it increases
If you answer I love you
Answer:B equals mass divided by volume
Explanation:I got hacks :)
Answer:
Which phrase describes air density? well b
increases as altitude increases
equals mass divided by volume
pushes molecules in one direction
exerts less pressure as it increases
Explanation:
love you too!!!!!
find the sum of 15, 9, 3, ....... 45
Answer:
hope this helps
Explanation:
72
3. Explain what would happen to the digestion process if enzymes were not present. SC.6.L.14.5
Unknown compound Q is spotted on a TLC plate that is then developed in dichloromethane. The solvent front is measured at 5.2 cm and the distance traveled by compound Q is measured at 3.4 cm. A sample of aspirin is spotted on a TLC plate that is then developed in dichloromethane. The solvent front is measured at 4.15 cm and the distance traveled by aspirin is measured at 2.70 cm. What can be determined about the identity of compound Q in light of this data
Answer:
Follows are the solution to the given question:
Explanation:
The Rf value on the Q is =0.65
The Rf value in the acetaminophen is =0.651
In this question, its identity the Q is probably in the acetaminophen since the value which is used to calculates, and however almost the same, and it is used to ensure the other document which is the substances, that are evaluated.
Which of the following statements best describes a
mixture?
O A substance that contains two or more elements chemically joined
O A substance that contains two or more elements not chemically joined
O A substance that contains only one type of atom
O A substance that contains two or more compounds or elements that are
not chemically joined.
The type of potential energy related to an object's height
Answer:
the answer is gravitational potential energy
Answer:
Since the gravitational potential energy of an object is directly proportional to its height above the zero position, a doubling of the height will result in a doubling of the gravitational potential energy. A tripling of the height will result in a tripling of the gravitational potential energy.
Explanation:
Hope this helps?
Which of the following is the correct decreasing order of hydrogen ions concentrations?
Answer: A> B> C > D> E
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
[tex]pH=-\log [H^+][/tex]
a) Solution A: pH =2
[tex][H^+]=10^{-2}[/tex]
b) Solution B: pH =5
[tex][H^+]=10^{-5}[/tex]
c) Solution C: pH = 7
[tex][H^+]=10^{-7}[/tex]
d) Solution D: pH = 8
[tex][H^+]=10^{-8}[/tex]
e) Solution E: pH =13
[tex][H^+]=10^{-13}[/tex]
Thus the decreasing order of hydrogen ion concentration is A> B> C > D> E
A severe storm would be most likely to damage a coastal area by causing
A.
volcanoes.
B.
pollution.
C.
erosion.
D.
earthquakes.
A severe storm would be most likely to damage a coastal area by causing pollution. Therefore, the correct option is option B.
What is coastal area?The region where land joins the ocean, or even as a line defining the border between the land as well as the shoreline, is known as the coast, sometimes referred as the coastline and seashore. The terrain of the area's surroundings has an impact on shorelines, as do water-induced erosion processes like wave action.
The length of the shoreline on Earth is about 620,000 kilometers. Natural ecosystems' coasts are significant zones and frequently the site of a diverse range of biodiversity. They are home to significant ecosystems on land, such as freshwater and estuarine wetlands, that are crucial for the survival of bird populations or other land animals. A severe storm would be most likely to damage a coastal area by causing pollution.
Therefore, the correct option is option B.
To know more about coastal area, here:
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What is the concentration of a 22.35 L solution that contains 9.95 moles of sodium
acetate? Round your answer to the correct number of significant figures.
Answer:
0.445 M
Explanation:
Molarity = moles/Volume
M = 9.95/22.35 = 0.445 M
Which materials allow electrons to flow through them?
A. Insulators only
B. Semiconductors and conductors
C. Conductors only
D. Semiconductors and insulators
The materials which allow electrons to flow through them are Semiconductors and conductors. Hence Option (B) is correct.
What are conductors ?A conductor, or electrical conductor, is a substance or material that allows electricity to flow through it.
In a conductor, electrical charge carriers, usually electrons or ions, move easily from atom to atom when voltage is applied.
Therefore, The materials which allow electrons to flow through them are Semiconductors and conductors. Hence Option (B) is correct.
Learn more about Conductor here ;
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Answer:semiconductors and conductors
Explanation:
I need help with like 35 questions anyone willing to help please let me know I have discord
UnknownGoddxss#2795
Please I only have like 5 hours to complete this
Answer and Explanation:
The molar mass of a substance is all of the weights from the elements combined.
So, we have the elements
CU, S, and [tex]O_{4}[/tex]
CU has a mass is 65
S mass is 32
O has a mass of 16, but there's 4 atoms of O, so we do 16 times 4, which is 64.
Now we add.
65 + 32 + 64 is 161.
So, the answer is 160, or answer choice A.
#teamtrees #PAW (Plant And Water)
Name the functional group in the
following molecule:
HSCH2CH3
A. alkane
B. amide
C. thiol
D. alkyl halide
Answer:
C. thiol
Explanation:
Answer:
it's C thiol I just took the test
hope this helps
have a good day :)
Explanation:
Balance Ca + HCI +CaCl2 + H2
Answer:
Ca + 2 HCl -- CaCl2 + H2
Explanation:
There are two hydrogen on the right side, so we multiply the left side( HCl) by 2 to get 2 hydrogen on the left. This automatically gives you 2 Cl on left side and there are already 2 cl on the right side, so now this equation is balanced.
2. I need to find the angle of corner of a room, what tool could I use?
a. Combination square
b. Plumb-bob
c. Sliding t-bevel
d. Tri-square
4. What is the specific heat of a substance if 5800 joules is
released in a 250 gram sample that will cool the substance from
60 degrees to 45 degrees?
Answer: 23.2
Explanation:
Which change represents an oxidation reaction?
What does this even mean? Help please and thank you!
Answer:
T₁ = P₁V₁T₂ / P₂V₂
Explanation:
The combine gas equation is given by:
P₁V₁ / T₁ = P₂V₂ / T₂
Where:
P₁ => is the initial pressure
V₁ => is the initial volume
T₁ => is the initial temperature
P₂ => is the final pressure
V₂ => is the final volume
T₂ => is the final temperature
Finally, we shall make T₁ the subject of the above expression. This can be obtained as follow:
P₁V₁ / T₁ = P₂V₂ / T₂
Cross multiply
T₁P₂V₂ = P₁V₁T₂
Divide both side by P₂V₂
T₁ = P₁V₁T₂ / P₂V₂
Thus, the formula for T₁ is:
T₁ = P₁V₁T₂ / P₂V₂
A substance that does not dissolve in a solvent is said to be:
A. insoluble
B. immiscible
C. miscible
D. soluble
Draw the structure formula for
1-ethyl-2,3-dimethylbenzene
Please help me
Answer:
Please see the attached picture.
Explanation:
1) Draw a benzene ring
2) On the first carbon, add a CH₂CH₃ (known as ethyl) since its location number is 1.
3) 'Dimethyl' refers to 2 methyl (CH₃) branches. The location numbers are 2 and 3, thus add a CH₃ on the 2nd and 3rd carbons.
*PLEASE HELP*
Write the word equation and the balanced symbol equation for the following reactions
1.Sulfuric acid reacting with sodium carbonate
2.Hydrochloric acid reacting with magnesium hydrogencarbonate
Answer:
1. H₂SO₄ + Na₂CO₃ ⇒ Na₂SO₄ + H₂O + CO₂
sulfuric acid + sodium carbonate ⇒ sodium sulfate + water + carbon dioxide
2. 2 HCl + Mg(HCO₃)₂ ⇒ MgCl₂ + 2 H₂O + 2 CO₂
hydrochloric acid + magnesium hydrogencarbonate ⇒ magnesium chloride + water + carbon dioxide
Explanation:
1. Sulfuric acid is H₂SO₄. Sodium carbonate is Na₂CO₃.
H₂SO₄ + Na₂CO₃ ⇒ Na₂SO₄ + H₂O + CO₂
sulfuric acid + sodium carbonate ⇒ sodium sulfate + water + carbon dioxide
2. Hydrochloric acid is HCl. Magnesium hydrogencarbonate is Mg(HCO₃)₂.
2 HCl + Mg(HCO₃)₂ ⇒ MgCl₂ + 2 H₂O + 2 CO₂
hydrochloric acid + magnesium hydrogencarbonate ⇒ magnesium chloride + water + carbon dioxide
Pls someone help rn!! Pls pls
Answer:
A. Mass = 61kg, weight on moon = 97.8N
Explanation:
To calculate the weight (force) from Mass of a body, the following formula is used:
W = mg
Where;
W = weight (Newtons)
m = mass (kg)
g = acceleration due to gravity (9.8m/s²)
According to this question, a scale shows that I weigh 600N on Earth, the mass on Earth can be calculated thus:
Using W = mg
m = W/g
m = 600/9.8
m = 61.2
m = 61kg
However, this mass on Earth will weigh differently on the Moon because gravity in the moon is 1.6 N/kg. The weight of the 61kg on the Moon is:
W(moon) = mass × gravity
W = 61 × 1.6
W = 97.6 N
Therefore, Mass = 61kg, weight on moon = 97.8N
g Hydrogen iodide, HI, decomposes at moderate temperatures according to the equation The amount of I2 in the reaction mixture can be determined from the intensity of the violet color of I2; the more intense the color, the more I2 in the reaction vessel. When 3.80 mol HI was placed in a 5.00-L vessel at a certain temperature, the equilibrium mixture was found to contain 0.443 mol I2. What is the value of Kc for the decomposition of HI at this temperature
Answer:
Equilibrium constant, Kc = 0.023
Explanation:
Equation for the decomposition of Hydrogen iodide is given below:
2HI ----> H₂ + I₂
Initially, the number of moles of the reactant and the products are given as follows:
n(HI) = 2 * 3.800 moles = 7.600 moles
nH₂) = 0.000 moles
n(I₂) = 0.000 moles
At equilibrium, the equation becomes: 2HI <----> H₂ + I₂
Number of moles of the reactant and the products are given as follows:
n(HI) = 7.600 - (0.886 + 0.886) moles = 5.828 moles
nH₂) = 2 * 0.443 = 0.886 moles
n(I₂) = 2 * 0.443 = 0.886 moles
Equilibrium constant, Kc = [H₂] [I₂] / [HI]²
Equilibrium constant, Kc = (0.886) * (0.886) / (5.828)²
Equilibrium constant, Kc = 0.023
Help plz now !
Which statement explains why a chemical equation must be balanced?
A. It must show the reactants and products on the correct sides of
the reaction arrow.
B. It must show that the mass of each element involved is conserved
by a chemical reaction.
C. It must show how each chemical formula is written to accurately
represent each substance.
D. It must show that coefficients and subscripts can be used in
chemical formulas.
Answer: B. It must show that the mass of each element involved is conserved by a chemical reaction.
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The correct statement why a chemical equation must be balanced is It must show that the mass of each element involved is conserved by a chemical reaction.
Answer:
B. It must show that the mass of each element involved is conserved
by a chemical reaction.
Explanation:
a p e x, just took the quiz
If I began this reaction with 1.7g of O2 , how much water would I make