Answer:
Theoretical yield = 0.1 g
Percent yield = 80%
Explanation:
Given data:
Mass of sodium = 2.3 g
Actual yield of hydrogen = 0.080 g
Theoretical yield = ?
Percent yield = ?
Solution:
Chemical equation:
2Na + 2H₂O → H₂ + 2NaOH
Number of moles of sodium:
Number of moles = mass/ molar mass
Number of moles = 2.3 g/ 23 g/mol
Number of moles = 0.1 mol
Now we will compare the moles of sodium with hydrogen to calculate the theoretical yield.
Na : H₂
2 : 1
0.1 : 1/2×0.1 = 0.05 mol
Mass of hydrogen produced:
Mass = number of moles × molar mass
Mass = 0.05 mol × 2 g/mol
Mass = 0.1 g
Percent yield of hydrogen:
Percent yield = actual yield / theoretical yield ×100
Percent yield = 0.08 g/ 0.1 g×100
Percent yield = 0.8×100
Percent yield = 80%
If Tracy were to put the pizza on the countertop to cool down, which temperature do you predict the pizza would get to?
a. -1 degrees Celsius
b. 10 degree Celsius
c. 27 degree Celsius
d. 93 degree Celsius
e. 260 degree Celsius
Answer:
d. 93 degree Celsius
Explanation:
Plzzzzzzzzzzzzzzzzzzzzzzz mark AS BRAINLIST
All of the following changes to a metal are physical changes except_____.
bending
melting
rusting
polishing
Answer:
D)Polishing..
Answer:
Wouldn't it be rusting
Explanation:
Melting and bending are physical changes so is polishing. so rusting is the only choice, for metal to rust wouldn't it need a chemical change.
How much MmHg are in 30.0 psi
Answer:
1551.45 MmHg
hope this helps :D
how many moles in 1.505x10^23 Na atoms
Answer:
The answer is 0.25 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question
N = 1.505 × 10²³ Na atoms
We have
[tex]n = \frac{1.505 \times {10}^{23} }{6.02 \times {10}^{23} } = \frac{1}{4} \\ [/tex]
We have the final answer as
0.25 molesHope this helps you
Pleaseee helpppp this is thermal energy in 6th rade and i need it quick for a formal assesment!!!!!!
Answer:The answer is B my child
Explanation:
Which properties of grains determine the texture of rocks? Check all that apply.
feel
pattern
color
shape
size
I will mark Brainlyest
Answer:
color shape and size
Explanation:
Each orbit of an atom contains a set number of..........
Answer:
I'm pretty sure it's electrons
Convert 2.6 x 106 mL to L.
Answer:
0.2756 L
Explanation:
0.2756 L
When iron reacts with oxygen, it forms iron oxide, or rust.
4 Fe + 3 O2 2 Fe2O3
If 112 g of iron (Fe) combines with 24 g of oxygen (O2), how much iron oxide is formed?
Answer:
Mass of iron oxide: 79.85 g
Explanation:
Given data:
Mass of iron = 112 g
Mass of O₂ = 24 g
Mass of iron oxide formed = ?
Solution:
4Fe + 3O₂ → 2Fe₂O₃
Number of moles of Fe:
Number of moles = mass/ molar mass
Number of moles = 112 g/ 55.85 g/mol
Number of moles = 2 mol
Number of moles of O₂:
Number of moles = mass/ molar mass
Number of moles = 24 g/ 32 g/mol
Number of moles = 0.75 mol
Now we will compare the moles of oxygen and iron with iron oxide.
Fe : Fe₂O₃
4 : 2
2 : 2/4×2 = 1
O₂ : Fe₂O₃
3 : 2
0.75 : 2/3×0.75 = 0.5
The number of moles of iron oxide formed by oxygen are less thus it will be limiting reactant.
Mass of iron oxide:
Mass = number of moles × molar mass
Mass = 0.5 mol × 159.69 g/mol
Mass = 79.85 g
Answer:
136 g Fe2O3
Explanation:
study island
C2H6O
Percent Composition with work shown
Answer:
50 percent
Explanation:
percentage
HELPPP
Which of the following pairs of elements is most likely to permanently transfer one or more electrons to the
other element?
a. Chlorine and phosphorus
b. Iron and bromine
c. Tin and lead
d. Nitrogen and oxygen
Describe the function of a cilia.
Answer:
hope it helps..
Explanation:
'Motile' (or moving) cilia are found in the lungs, respiratory tract and middle ear. ... These cilia have a rhythmic waving or beating motion. They work, for instance, to keep the airways clear of mucus and dirt, allowing us to breathe easily and without irritation.
Answer: to keep airway clear of mucus and dirt allowing us to breathe easy
Explanation:
16. The diffusion rate of an unknown gas is measured to be 31.50 mL/min. Under
identical conditions, the diffusion rate of oxygen gas is measured to be 30.50
mL/min. Hint: diffusion rate is directly related to velocity.
Determine the identity of the unknown gas from the following options:
a. CH4
b. CO
C. NO
d. CO2
e. NO2
Answer:
Explanation:
[tex]\frac{r_1}{r_2} = \sqrt{\frac{M_2}{M_1} }[/tex]
r₁ and r₂ are rate of diffusion of gas having molecular mass of M₁ and M₂
[tex]\frac{31.5}{30.5} = \sqrt{\frac{32}{M_1} }[/tex]
1.0666 = 32 / M₁
M₁ = 30
molecular weight of NO = 14 + 16 = 30
So the unknown gas is NO .
__is a term that refers to the amount of space that a substance or an object takes up
Refer to the Chemical Compounds table above. How many total elements are in
Ethanol?
Answer:
3 element i.e carbon (C), hydrogen (H) and oxygen.
Explanation:
The following data were obtained from the question:
Subtance >>>>>>>> Chemical Formula
Glucose >>>>>>>>> C₆H₁₂O₆
Methane >>>>>>>> CH₄
Ethanol >>>>>>>>> C₂H₅OH
Hydrogen peroxide >> H₂O₂
From the above table, we can see that ethanol (C₂H₅OH) contains carbon (C), hydrogen (H) and oxygen
Therefore, the total number of elements present in ethanol, C₂H₅OH is 3.
100 POINTS HELP!!!!!!!!!!!!!!!!!!!!
Given that,
Mass number of Ge = 70
Then,
Atomic number of Ge = 32
No. of protons = 32
No. of electrons = 32
No. of neutrons,
→ 70 - 32 = 30
Answer:
30 is correct
Explanation:
70 - 32 = 30 mark as brainliest
What is another name for radioactive dating?
Answer:
radioisotope dating is another name
Answer:
Radiometric dating
Explanation:
hope that helps
which type of wave shows energy transmitted in a definite direction and with a definite speed?
answer this question
Answer:
The first one
Explanation:
What are the four main types of tissues in the human body?
epithelial
dermal
vascular
connective
muscle
nervous
Convert 3564 to Scientific Notation:
*
Answer:
3564 = 3.564 x 10^3
Explanation:
i.e expresing the value in standard form.
What is the process that occurs when repeated freezing and thawing breaks apart rocks?
Erosion
Deposition
Physical weathering
Chemical weathering
Answer:
C. Physical weathering.
Answer: C. Physical weathering.
Explanation:
In chemistry lab, a student measured the density of liquid ethanol is 0.789 g/mL. Represent its density in units of 1b /in3? (2.54 cm = 1 in., 2.205 lb = 1 kg)
A. 9.09 x 10+ 1b / in
B.4.42 x 10-1b / in?
OC.2.85 x 10-2 16 / in
D. 0.106 16 / in?
O E.5.86 x 10" 16/in3
Answer:
Option C is correct option = 2.85×10⁻² lb/in³
Explanation:
Given data:
Density in g/mL = 0.789
Density in lb/in³ = ?
Solution:
It is given that,
2.54 cm = 1 in
2.205 lb = 1 kg thus,
1 mL = 1 cm³
0.789 g/cm³ × 1 kg/ 1000 g × 2.205 lb/1 kg × (2.54 cm / 1in)³
2.85×10⁻² lb/in³
The density of liquid ethanol is 0.789 g/mL, which is equivalent to 0.0285 lb/in³.
A student measured the density of liquid ethanol to be 0.789 g/mL and we want to convert it to lb/in³. We will need a series of conversion factors.
What is a conversion factor?A conversion factor is an arithmetical multiplier for converting a quantity expressed in one set of units into an equivalent expressed in another.
Step 1: Convert 0.789 g/mL to lb/mLWe will use the following conversion factors:
1 kg = 1000 g.1 kg = 2.205 lb.0.789 g/mL × (1 kg/1000 g) × (2.205 lb/1 kg) = 1.74 × 10⁻³ lb/mL
Step 2: Convert 1.74 × 10⁻³ lb/mL to lb/in³We will use the following conversion factors:
1 mL = 1 cm³.1 in = 2.54 cm.1.74 × 10⁻³ lb/mL × (1 mL/1 cm³) × (2.54 cm/1 in)³ = 0.0285 lb/in³
The density of liquid ethanol is 0.789 g/mL, which is equivalent to 0.0285 lb/in³.
Learn more about unit conversion here: https://brainly.com/question/13016491
The vaporization of Br2 from the liquid to the gas state requires 7.4 kcal/mol. write a reaction showing heat as a product or reactant
Answer:
Br₂(l) + ΔV → Br₂(g)
Explanation:
When a chemical or phase change occurs during a chemical process some heat is absorbed or released. For the process of vaporization of a substance, the heat (Usually required) is ΔV (How many energy is required for the process occurs).
In the vaporization of Br2 there are required 7.4kcal/mol, Δv. The reaction is:
Br₂(l) + ΔV → Br₂(g)Help me lol
I’ll give branliest if two people answer
Answer:
I think all of the above
Explanation:
Put as brainliest if you wish
When does a single-displacement reaction occur?
A. When a substance, usually containing carbon, reacts with oxygen
to produce energy in the form of heat and light
B. When one element replaces another element in a compound
during a chemical reaction
C. When a substance is broken down into two or more simpler
substances in a chemical reaction
D. When a single element forms two double elements
Answer:
B. When one element replaces another element in a compound during a chemical reaction
I would like some help on this please.
Answer:
Both b and c i think so... .
I think it is the dark blue tile because if it is not soluble, or insoluble, then it will not dissolve and you will still see it floating around in the liquid or at the bottom of the container.
What is matter?
A.
Anything that has energy
B.
Anything that changes volume
C.
Anything that takes up space
D.
Anything that produces heat
a b c or d no bull
Answer:
C. Anything That Takes Up Space.
Explanation:
A 10.151 g sample of window cleaner containing ammonia was diluted with 39.466 mL of water. Then 4.373 g of solution was titrated with 14.22 mL of 0.1063 M HCl to reach a bromocresol green end point. Find the weight percent of NH3 (FM 17.031) in the cleaner.
Answer:
2.878 (w/w)%
Explanation:
The reaction of NH3 with HCl is:
NH3 + HCl → NH4Cl
That means 1 mole of ammonia reacts per mole of HCl. The moles of HCl that reacts = Moles of ammonia are:
14.22mL = 0.01422L * (0.1063mol HCl / L) = 0.001512 moles HCl = Moles ammonia
In mass:
0.001512 moles NH3 * (17.031g / mol) = 0.02574g of NH3 in the solution.
The concentration in weight percent of the diluted solution is:
0.02574g of NH3 / 4.373g * 100 = 0.5887 (w/w)%
This is the concentration of the diluted solution that was diluted from 10.151g to 10.151g + 39.466g = 49.617g
-Assuming density of water = 1g/mL-
The solution was diluted:
49.617g / 10.151g = 4.888 times.
That means the concentration of NH3 in the original cleaner is:
0.5887 (w/w)% * 4.888 =
2.878 (w/w)%A person drops two objects from the same height. one object weighs 15 N and the other weighs 10 N
A The 10 N object has the same mass as the 15 N object
B The 15 N object has twice the mass of the 10 N object
C The 15 N object has more mass than the 10 N object
D The 10 N object has more mass than the 10 N object