A 0.6113-g sample of Dow metal, containing aluminum, magnesium, and other metals, was dissolved and treated to prevent interferences by the other metals. The aluminum and magnesium were precipitated with 8-hydroxyquinoline. After filtering and drying, the mixture of Al(C9H6NO)3 and Mg(C9H6NO)2 was found to weigh 7.8154 g. The mixture of dried precipitates was then ignited, converting the precipitate to a mixture of Al2O3 and MgO. The weight of this mixed solid was found to be 1.0022 g. Calculate the %w/w Al and %w/w Mg in the alloy
Answer:
95.55% w/w Mg; 2.89% w/w Al
Explanation:
We can solve this question using both precipitates mixture. for example, for the oxide:
Mass MgO + Mass Al2O3 = 1.0022g
Moles MgO*40.3044g/mol + Moles Al2O3*101.96g/mol = 1.0022g
Where we are writting the molar mass of each oxide.
We can write, thus:
40.3044X + 50.98Y = 1.0022 (1)
Where X are moles of Mg and Y moles of Al
Because 1 mole of Al2O3 are 2 moles of Al
And for the other mixtue:
312.605X + 459.4317Y = 7.8154 (2)
Replacing (2) in (1):
312.605(1.0022-50.98Y / 40.3044) + 459.4317Y = 7.8154
312.605(0.024866-1.26487Y) + 459.4317Y = 7.8154
7.7732 - 395.406Y + 459.4317Y = 7.8154
64.0257Y = 0.0422
Y = 6.591x10⁻⁴ moles = Moles Al
The moles of Mg are:
312.605X + 459.4317*6.591x10⁻⁴ moles = 7.8154
312.605X + 0.3028 = 7.8154
312.605X = 7.5126
X = 0.02403 Moles = Moles Mg
The mass of each metal and its mass percent is:
Mg: 0.02403moles * (24.305g/mol) = 0.5841g / 0.6113g * 100 =
95.55% w/w MgAl: 6.591x10⁻⁴ moles * (26.98g/mol) = 0.01767g / 0.6113g * 100 =
2.89% w/w Al15. The equation which gives the
relationship between the cell potential
and the concentrations of the cell
components is called -- (a) Nernst
equation (b) likovicequation (c) Voltaic
equation (d) none of the above
Which of these is not a reason for using a placebo?
A. So that the effect of a patient's mind is taken into account in the
drug testing
B. To determine which of two pills is a better choice for treating a
disease
C. So that all patients will believe their disease is being treated
D. To have a control group to test the drug's effectiveness against a
disease
SUBMIT
Answer: B. To determine which of the two pills is a better choice for treating a disease
Explanation: A placebo will have no effect thus comparing it with a drug would be obsolete.
Answer:
So that all patients will believe there disease is being treated
Explanation:
APEC!
how many atoms in 2.25 mol of O2
Answer:
1 molecule of oxygen has 2 atoms.
So 2,25 molecules of oxygen have 2 x 2,25 atoms.
2 x 2,25 = 4,5 atoms
There are 4,5 atoms in 2,25 molecules oxygen.
Aside from direct harm, what secondary issue do invasive species present?
They may be able to eat all kinds of native organisms.
They may not have any predators.
They might damage the habitat that other organisms rely on.
They might introduce other organisms like viruses and bacteria.
Answer:
They may not have any predators.
Explanation:
Look at the electron-dot diagram. What type of bond would two sulfur atoms require to form a molecule?
single covalent bond
double covalent bond
triple covalent bond
quadruple covalent bond
Answer:
Double Covalent
Explanation:
When two of the same element combine it will always be a covalent bond between them and since sulfur has two lone electrons it will make a double bond between the two to have a full octect
what are genetic factors?
How should this combustion reaction be balanced?
C5Hg + 02 → C02 + H2O
A. C5Hg + 502 → 5C02 + H2O
B. C5H9 +3.502 → 5CO2 + 8H20
C. C5Hg + 702 → 5CO2 + 4H20
D. C5Hg + 302 → CO2 + 4H20
Answer:
Answer is C. C5H8 + 7O2 -> 5CO2 + 4H2O
There are 4.67 * 10 ^ 24 hydrogen gas molecules the react with 21.0 Liters of oxygen gas STP conditions to form water. How many grams of water will form? How many moles of the excess reactant will remain after the reaction is completed?
Answer:
I am almost done
Explanation:
21.0 L
↓
2H₂(g) + O₂(g) → 2H₂O(l)
↑
4.67 × 10²⁴ moles
[This is done so the equation is balanced and the reaction can occur]
[subscripts are the number of atoms, and the coefficients are the number of molecules]
______________
Since there are about 6.02 × 10²³ moles in one mol of a substance.
4.67 × 10²⁴ / 6.02 × 10²³ =
7.7547174437 mol.
Next, we must determine the grams per mole of each substance, this can be done with the periodic table.
Since hydrogen, and oxygen gas are diatomic, they will consist of two atoms each. So the atomic mass will be multiplied by 2 to get the molecular mass. Therefore H₂ will have a molecular mass of 1.00794 × 2 = 2.01588 g/mol.
Calculate the mass of 1 Mole of Copper(ii) sulfate pentahydrate
200 g CuSO₄ · 5H₂O
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Reading a Periodic TableMolesCompoundsOrganic
Prefix rootsReactions
SaltsAnhydride SaltsHydratesStoichiometry
Using Dimensional AnalysisExplanation:Step 1: Define
[Given] 1 mol CuSO₄ · 5H₂O (Copper II sulfate pentahydrate)
Step 2: Identify Conversions
[PT] Molar Mass of Cu - 63.55 g/mol
[PT] Molar Mass of S - 32.07 g/mol
[PT] Molar Mass of O - 16.00 g/mol
[PT] Molar Mass of H - 1.01 g/mol
Molar Mass of CuSO₄ - 63.55 + 32.07 + 4(16.00) = 159.62 g/mol
Molar Mass of H₂O - 2(1.01) + 16.00 = 18.02 g/mol
Step 3: Convert
There is 5 moles of water added for every one mole of Copper II Sulfate present.
[DA] Set up: [tex]\displaystyle 1 \ mol \ CuSO_4(\frac{159.62 \ g \ CuSO_4}{1 \ mol \ CuSO_4}) + 5 \ mol \ H_2O(\frac{18.02 \ g \ H_2O}{1 \ mol \ H_2O})[/tex][DA] Multiply/Divide [Cancel out units]: [tex]\displaystyle 159.62 \ g \ CuSO_4 + 90.1 \ g \ H_2O[/tex][DA] Add: [tex]\displaystyle 249.72 \ g \ CuSO_4 \cdot 5H_2O[/tex]Step 4: Check
Follow sig fig rules and round. We are given 1 sig fig.
249.72 g CuSO₄ · 5H₂O ≈ 200 g CuSO₄ · 5H₂O
In which compound does the first element have an ion charge of 1+?
1.)
CoCl2
2.)
ClF3
3.)
ZnO
4.)
Au2S
Answer:
#4 is the correct answer
Explanation:
For #1, Cobalt has an ionic charge of +2
Chloride has a charge of -1, and Zinc has an ionic charge of +2. Therefore, Au has a charge of +1
Will give brainliest!!!!
Answer:
446 mmHg
Explanation:
From the question given above, the following data were obtained:
Total pressure (Pₜ) = 871 mmHg
Partial pressure of He (Pₐ) = 281 mmHg
Partial pressure of N₂ (P₆) = 144 mmHg
Partial pressure of O₂ (P꜀) =?
The partial pressure of O₂ can be obtained as follow:
Pₜ = Pₐ + P₆ + P꜀
871 = 281 + 144 + P꜀
871 = 425 + P꜀
Collect like terms
P꜀ = 871 – 425
P꜀ = 446 mmHg
Therefore, the partial pressure of O₂ in the mixture is 446 mmHg
Karl went to the doctor complaining of a sore throat. The doctor performed
a throat culture and determined that antibiotics were not necessary. The
doctor told her to drink tea, take ibuprofen, and rest. Which type of microorganism most likely caused Karl's sore throat?
a) bacteria
b) virus
c) parasite
d) fungi
Answer:
A
Explanation:
bc
Calculate P[NO]eq, if P [NOCI]eq = 0.33 atm, P [C12]eq = 0.50 atm, and Kp = 1.9 x 10-2.
2 NOCI(g) = 2 NO(g) + C12(g)
Answer:
0.064 atm. that's the answer
Find the molarity of a 8.9M KOH solution if 76 ml of solution is diluted to 171 ml?
3.96m
20.03M
0.25m
3.96M
Heeeellllppppp meeee pls
Answer:
3.96 M
Explanation:
Step 1: Given data
Concentration of the concentrated solution (C₁): 8.9 MVolume of the concentrated solution (V₁): 76 mLConcentration of the diluted solution (C₂): ?Volume of the diluted solution (V₂): 171 mLStep 2: Calculate the concentration of the diluted solution
We can calculate the concentration of the diluted solution using the dilution rule.
C₁ × V₁ = C₂ × V₂
C₂ = C₁ × V₁/V₂
C₂ = 8.9 M × 76 mL/171 mL = 3.96 M
give the symbols of the ions formed when sodium reacts with chlorine
Answer:
When a sodium atom transfers an electron to a chlorine atom, forming a sodium cation (Na+) and a chloride anion (Cl-), both ions have complete valence shells, and are energetically more stable.
can somebody please help me ! :(
Answer:
325
Explanation:
velocity = 3250 Hz x 0.1 m
Answer:
325
Explanation:
Science**
5) Which statement best states the relationship between mass and
gravitational attraction between two objects? *
The less mass an object has, the greater its gravitational force.
Dose Anabolic Reaction helps cells multiply and stay good condition
DO NOT JUST USE UP THE POINTS I WILL REPORT YOU
tell me if your from connexus please with your answer
I have ten moles of iron atoms in the reactant side of a reaction. Do I have enough information to determine how many moles of iron atoms I will have following the reaction? If so, how many moles of iron atoms will I have at the end of a reaction? If not, what else do I need to know?
Answer: You will have 10 iron moles
Explanation: This is due to the law of conservation of mass. The amount of atoms going in the reactant side of a reaction has to be equal to the amount of atoms in the product side
Which rock type(s) could be transformed into sediment?
a: sedimentary rock
b. igneous rock
c. both rock types
d. neither rock types
Answer:
b!
Explanation:
Answer:
c - both rock types
Explanation:
when weathered and eroded they can become sediments!
1.
In the periodic table, all the elements in the same column have similar
and
properties.
Answer:
same ammount of electrons
Explanation:
hope this helps:)
Which of the following hypotheses is incorrect?
A I UV light can damage the eyes, then UV light may be the cause of blindness.
B.
The length of the string has an effect on the time of the oscillation. As the length shortens, the time taken for one oscillation also decreases.
If the diffusion rate through a membrane is related to the molecular size, then smaller the molecule, the faster it will pass through a membrane.
D
Soft drinks are acidic because of the presence of citric acid and phosphoric acid.
Answer:
A
Explanation:
uv light doesn't cause permanent blindness rather causes a condition known as Photokeratitis.
photokeratitis is a painful condition caused by uv light to the eye.
1. Goose
2.frog
3. Turkey
4.earthworm
Answer:
Goose
Explanation:
following yes on the key,
feather: yes -> swims
Swims: yes -> goose
what voltage is required to move 2a through 20ω
Answer:
10 volts
Explanation:
V= P/I
V = 20/2 = 10 volts
When drawing the Lewis structure of a molecule, start by determining the total number of available valence based on each element's ____________ Then, use the total number of electrons needed for each element to be stable, generally based on __________ to determine the _____________ by finding the difference between the number of needed and available electrons divided by two. Next, identify the central atom, which is the element with the ______________ other than hydrogen. Finally, arrange the number of bonds around the central atom to fulfill the stable number of electrons for each element.
Answer:
group number
the octet rule
total number of bonds
fewest valence electrons
Explanation:
When drawing the Lewis structure of a molecule, start by determining the total number of available valence based on each element's group number Then, use the total number of electrons needed for each element to be stable, generally based on the octet rule to determine the total number of bonds by finding the difference between the number of needed and available electrons divided by two. Next, identify the central atom, which is the element with the fewest valence electrons other than hydrogen. Finally, arrange the number of bonds around the central atom to fulfill the stable number of electrons for each element.
A sound wave has a frequency of 3250 Hz and a
wavelength of 0.1 m. What is its velocity? SHOW
YOUR WORK
help please!!
Answer:
c = 325.0 m/s.
Explanation:
Hello there!
In this case, since the frequency, velocity and wavelength are related via:
[tex]c=\lambda *f[/tex]
Whereas c is the velocity, lambda the wavelength and f the frequency. Thus, we plug in the given data to obtain:
[tex]c=3250s^{-1}*0.1m\\\\c=325.0m/s[/tex]
Best regards!
Hydrochloric acid is a ———— ?
A. Strong electrolyte
B. Weak electrolyte
C. Non-electrolyte
D.
E. Molecular compound
Answer:
A is the answer
Explanation:
Pls mark BRAINLIEST
Consider the following diagram of a chemical reaction.
A series of four increasingly more complex chemical structures. The first diagram shows that when heat is applied to R single bond O single bond O single bond R, it creates 2 R single bond O with 1 electron dot. The next structure brings in more complex structures and other atoms, such as H and C. This process continues until the final molecule has a long chain of six starting with R O and ending with C with a single electron dot. There are four single side chains, 3 P h and 1 H.
What is the product that is formed in this reaction?
a polymer
a monomer
an alkyl halide
a carboxylic acid
Answer:
The answer is A
Explanation:
on EDG 2021
Answer:A
Explanation:
What is 0.00000005 in scientific notation, rounded to two significant figures?
Answer:
5×-10^8
That is the the scintific notation for 0.00000005
Answer=5×-10^8