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Related Questions
What is the empirical formula for a compound that is comprised of 54.0% sodium, 8.50% boron, and 37.5% oxygen by mass?
A) Na2B2O3.
B) Na3BO3.
C) Na3B2O2.
D) Na4BO4.
Answers
Answer:
B) Na3BO3.
Explanation:
Hello!
In this case, since percent compositions are used to identify the empirical formula of an unknown compound, we can assume we have 54.0 g of sodium, 8.50 g of boron and 37.5 g of oxygen, and we compute the moles of each one:
[tex]n_{Na}=54.0g*\frac{1mol}{23g} =2.35mol\\\\n_B=8.50g*\frac{1mol}{11g}=0.773mol\\\\n_O=37.5g*\frac{1mol}{16g}=2.34mol[/tex]
Now, we divide by the moles of boron as those are the fewest:
[tex]Na:\frac{2.35}{0.773}=3\\\\B:\frac{0.773}{0.773}=1\\\\O=\frac{2.34}{0.773}=3[/tex]
Thus, the empirical formula is B) Na3BO3.
Best regards!
Most of the elements in the periodic table can be described as:
A. metalloids
B. halogens
c. non-metals
D. metals
Answers
The answer would be metals :)
Rust has the same properties as iron
True
False
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Answer:
false
Explanation:
i need the answer for this
Answers
Answer:
need points
Explanation:
how many elements are found in the third period. A.2 B.18 C.8 D.32
Answers
Answer:
8
Explanation:
u can find it on ur chemistry book
Answer:
C. 8
Explanation:
Check chemistry textbook
Why is it important to know which category of microorganism has caused an infection?
Select one:
a. Treatment depends on which kind of organism caused the infection.
b. Probiotic infections can actually worsen some conditions.
c. Some infections can indicate cancer.
d. Some types of infections are highly contagious.
PLEASE ANSWER QUICKLY
Answers
Answer:
A
Explanation:
The percent by mass of Ca in CaCl2 is equal to
1. (40/111) x 100
2. (111/40) x 100
3. (3/1) x 100
4. (1/3) x 100
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Answer:
(40/111)×100Here is a bonus Answer✍️✍️Percent composition by elementElement Symbol Mass PercentChlorine Cl 63.888%Calcium Ca 36.112Mass percentage does not have any unit as numerator and denominator contains the same unit. The percent by mass of Ca in CaCl[tex]_2[/tex] is equal to (40/111) x 100. The correct option is option A.
What is percentage by mass?Mass percentage represents the the percentage of each element that is making a particular compound.
Mathematically,
Percentage of mass = (component’s mass ÷ total mass) x 100%
Atomic weight of different element of calcium chloride{ CaCl[tex]_2[/tex]} are
Ca = 40 ; Cl = 35
Total mass of Calcium element in calcium chloride = 40g/mol
Total mass of Chlorine atom in calcium chloride = 35× 2= 71g/mol
Total molar mass of calcium phosphate = 40 +71= 111g/mole
Percentage of calcium in calcium chloride =40÷111 = 36%
Therefore, the percent by mass of Ca in CaCl2 is equal to (40/111) x 100. The correct option is option A.
To learn more about mass percentage, here:
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100
80
100 mL
water vapor
Which statement describes what will happen if a student pushes the plunger
to compress the water vapor?
A. The total number of water particles will increase.
B. The amount of energy in the water particles will decrease.
C. The amount of empty space between the water particles will
decrease
D. The total volume of the water particles will increase
I will mark brainliest
Answers
Answer:
Explanation:it is c
Answer:
C The amount of empty space between the water particles will decrease
Explanation:
I just took the quiz, have a nice day!
FeO+ PdF2 ---> FeF2+PdO balance please worth 50 points
Answers
Answer: FeO
Explanation:
Answer:
This is not worth 50 points liar
Explanation:
The free flow of electrons is responsible for
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Answer:
An electrical phenomenon is caused by flow of free electrons from one atom to another. The characteristics of current electricity are opposite to those of static electricity. Wires are made up of conductors such as copper or aluminum.
Explanation:
from google
Why are standard electrode potentials usually measured at 1.0 M electrolyte concentration?
Answers
Answer:
To avoid variation due to concentration
Explanation:
Hope this helps :)
When [H+] = 4.0 × 10–9 M in water at 25°C, then
Kw =1.0×10–14.
b. pOH = 7.
c. [H3O+] = [OH–].
d. pH= 7
e. A-D are all correct
Answers
Answer:
a. Kw = 1.0 × 10⁻¹⁴
Explanation:
a. Let's consider the self-ionization of water.
2 H₂O(l) ⇄ H₃O⁺(aq) + OH⁻
The ion-product of water (Kw) at 25 °C is:
Kw = [H₃O⁺][OH⁻] = 1.0 × 10⁻¹⁴
c. Considering [H⁺] = [H₃O⁺] = 4.0 × 10⁻⁹ M, the concentration of OH⁻ is:
[OH⁻] = 1.0 × 10⁻¹⁴/[H₃O⁺] = 2.5 × 10⁻⁶ M
b. We can calculate the pOH using the following expression.
pOH = -log [OH⁻] = -log 2.5 × 10⁻⁶ = 5.6
d. We can calculate the pH using the following expression.
pH = -log [H⁺] = -log 4.0 × 10⁻⁹ = 8.4
When [H+] = 4.0 × 10–9 M in water at 25°C, then the [tex]Kw =1.0\times 10^-^1^4.[/tex]
What is dissociation constant?
Kw is the dissociation constant or ionization constant of water.
The self-ionization of water will be
[tex]\rm 2 H_2O(l) = H_3O^+(aq) + OH^-[/tex]
The dissociation constant of the water at 25°C will be
[tex]\rm Kw = [H_3O^+][OH^-] = 1.0 \times 10^-^1^4[/tex]
Thus, the correct option is a. [tex]Kw =1.0\times 10^-^1^4.[/tex]
Learn more about dissociation constant
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help me pleaseeeeee
Answers
Answer:
Arthropod (3)
Annelids (2)
Cnidarians (1)
Echinoderms (4)
Explanations:
I hope all this helps if u don't understand it let me know.
1. What kinds of metals are REALLY reactive? why?
2. What kinds of non-metals are REALLY reactive? why?
3. What group on the periodic table doesn’t react at all? why?
Answers
Answer:
1. Alkali metals (group 1)
2. halogens (Group 17)
3. noble gasses (group 18)
Explanation:
1. alkali metals only have one valence electron meaning that they really want to lose that one valence electron to get a full octet.
2. halogens have 7 valence electrons meaning that they just need to gain 1 to get a full octet.
3. Nobel gasses already have a full octet meaning that they don't want to react. (atoms only react to get a full octet)
I hope this helps. Let me know if anything is unclear.
Adaleigh is learning about renewable and non-renewable resources in her science class. She decides to take
a nature walk and makes notes of all the renewable resources that she sees. Which of the following is an
observation that Adaleigh could have made on her walk?
A. The seeds on the ground are going to grow into new trees.
B. The tallest trees had the most seeds around their bases.
C. When trees decay, they could eventually turn into coal.
D. Pine trees are older than oak trees.
Answers
Answer:
A. The seeds on the ground are going to grow into new trees.
Explanation:
Trees are renewable resources.
Question 5
2 pts
To determine the density of an irregularly shaped object, a student immersed the object in 32.2 mL of water in a graduated cylinder, causing the level of the water to rise to 37.8 ml. If the object had a mass of 12.4 g, what is the density of the object?
O 0.32 g/mL
O 1.4 g/mL
O 3.4 g/mL
O 2.2 g/mL
Help quick right answer gets brainliest !!
Answers
Answer:
Explanation:
2.2 g/mL is the answer.
Which molecule/molecular compound is joined by a single covalent bond? O2 or N2 or Br2 or CO2?
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HELPPPPPPPPP 35 POINTSSSSSS!!!!!FILL IN THE BLANKS with either "reduce" or "oxidize"
Magnesium is able to ——copper, and copper is able to —— magnesium.
Zinc is able to—— magnesium, and magnesium is able to—— zinc.
Copper is able to—— zinc, and zinc is able to—— copper.
Answers
Look at my screenshot:
How are ionic compounds named?
Answers
Answer:
Ionic compounds are neutral compounds made up of positively charged ions called cations and negatively charged ions called anions. For binary ionic compounds (ionic compounds that contain only two types of elements), the compounds are named by writing the name of the cation first followed by the name of the anion.
Explanation:
Hope this helps.
When is my dad going to get the milk?
Answers
Answer:
joe.......
Explanation:
mama......
A 2.52 L container of oxygen gas at 28.6 °C is heated to 45.9 °C. Assuming that the volume of the container can vary, what is the new volume of the gas?
Answers
Answer:
4.04433566 L (433566 repeating)
Explanation:
2.52 is divided by 28.6 is 0.0881118 (881118 repeating). multiply 0.0881118 (881118 repeating) by 45.9 to get 4.04433566 L (433566 repeating).
A. What is the frequency of light that has a wavelength of 6.2 x 10^-7 m?
B. Identify the color of this light.
C. Calculate the amount of energy given off by this atom.
Answers
Answer:
I think the answer is letter C
Compare and contrast the mass of the object to the size of the object.