Answer:
4.2 g
Explanation:
Select the correct answer.
For Al, its atomic number is 13 and its mass number is 27. How many neutrons does it have?
Ο Α. .
13
ОВ.
14
26
OD
27
O E
40
Answer:
B.) 14
Explanation:
27-13=14 neutrons
Please someone help I’m really confused
Answer:10-3
Explanation:
PLEASE ANSWER!!!!!!!!
Scientists observe the polyatomic ion nitrate forming a compound with unknown element 'A' and predict that the chemical formula could be A2NO3. One of the scientists, Nadeen, states that this chemical formula would be impossible. Is Nadeen correct? Explain why or why not.
Answer:
knflnvwlknnffenfkw
Explanation:
Water decomposes to hydrogen and oxygen gas as shown in
the following reaction:
2H20 (g) → 2H2 (g) + O2 (g)
Given a 6.80 g sample of H20 (MM = 18.0 g/mol), how many
grams of oxygen (MM = 32.0 g/mol) is produced, assuming the
decomposition goes to completion?
Answer:
6.04 g O2
Explanation:
6.80 g H2O x (1 mol/18.0 g) x (1 O2/2 H2O) x (32.0 g/1 mol) = 6.04 mol O2
Ca and F what are the name of the ionic compounds
Answer:
Calcium flouride?
Explanation:
Quite self explanatory
Describe Muller's Ratchet.
Answer:
Muller's ratchet is a paradigmatic model in population genetics which describes the fixation of a deleterious mutation in a population of finite size due to an unfortunate stochastic fluctuation.
Explanation:
Answer:
Muller's ratchet is a paradigmatic model in population genetics which describes the fixation of a deleterious mutation in a population of finite size due to an unfortunate stochastic fluctuation.
Explanation:
This is the correct answer took a test and got this correct thank you to the original user above.
Determine how many molecules are in 86L of carbon dioxide at STP?
Answer:How can you tell how much gas is in these containers?
Small gas tanks are often used to supply gases for chemistry reactions. A gas gauge will give some information about how much is in the tank, but quantitative estimates are needed so the reaction will be able to proceed to completion. Knowing how to calculate needed parameters for gases is very helpful to avoid running out too early.
Conversions Between Moles and Gas Volume
Molar volume at STP can be used to convert from moles to gas volume and from gas volume to moles. The equality of 1 mole = 22.4 L is the basis for the conversion factor.
Sample Problem One: Converting Gas Volume to Moles
Many metals react with acids to produce hydrogen gas. A certain reaction produces 86.5 L of hydrogen gas at STP. How many moles of hydrogen were produced?
Step 1: List the known quantities and plan the problem.
Known
86.5 L H2
1 mol = 22.4 L
Unknown
moles of H2
Apply a conversion factor to convert from liters to moles.
Step 2: Calculate.
Explanation:
Which type of cell can have a flagellum or cilia
Answer:
Both prokaryotic and eukaryotic cells contain structures known as cilia and flagella. These extensions from the cell surface aid in cell movement. They also help to move substances around cells and direct the flow of substances along tracts. Cilia and flagella are formed from specialized groupings of microtubules called basal bodies.
Explanation:
Where is the arctic tundra biome found?
Use this website to answer the question: https://thewildclassroom.com/biomes/artictundra-2/
Question 2 options:
Almost entirely in the Northern Hemisphere, from 60 to 70 degrees latitude North.
In tropical and subtropical latitudes
In high altitudes
Within tropical and subtropical latitudes
Answer:
In high altitudes
Explanation:
hope it helps you
The artic tundra biome is found in high altitudes.
What is arctic tundra biome?Artic tundra biome is the northernmost biome, which covers the land of the arctics with the ice caps.
Climate of this Artic tundra biome is almost cold means the temperature in winter season of this region is about -34 degree celsius and temperature in summer season of this region is about 3 - 12 degree celsius. And it observed generalyy on the northen side.
Hence correct option is (C).
To know more about Artic tundra biome, visit the below link:
https://brainly.com/question/4125133
An object was measured by a worker as
15.9cm long, however, the manufacturer
specifications list the length of the object at
15.8cm. What is the percent error in the
workers measurement?
Answer:.633
Explanation:
I have know idea but it was right
Answer:
O.633%
Explanation:
For all those Acellus kids XD
A mixture of 65 percent N2 and 35 percent CO2 gases (on a mass basis) enters the nozzle of a turbojet engine at 60 psia and 1400 R with a low velocity, and it expands to a pressure of 12 psia. If the isentropic efficiency of the nozzle is 88 percent, determine:
(a) the exit temperature
(b) the exit velocity of the mixture.
Assume constant specific heats at room temperature.
Answer:
a. 969.1 R
b. 2237 ft/s
Explanation:
First the apparent specific heats are determined from the mass fractions of the gases:
[tex]c_{p} &=\left(\mathrm{mf} c_{p}\right)_{\mathrm{N}_{2}}+\left(\mathrm{mf} c_{p}\right) \mathrm{CO}_{2} \\ &=(0.65 \cdot 0.248+0.35 \cdot 0.203) \frac{\mathrm{Btu}}{\mathrm{lbm} \mathrm{R}} \\ &=0.232 \frac{\mathrm{Btu}}{\mathrm{lbmR}} \\ c_{v} &=\left(\mathrm{mf} c_{v}\right)_{\mathrm{N}_{2}}+\left(\mathrm{mf} c_{v}\right)_{\mathrm{CO}_{2}} \\ &=(0.65 \cdot 0.177+0.35 \cdot 0.158) \frac{\mathrm{Btu}}{\mathrm{lbmR}} \\ &=0.170 \frac{\mathrm{Btu}}{\mathrm{lbmR}}[/tex]
The isentropic coefficient then is:
[tex]k &=\frac{c_{p}}{c_{v}} \\ &=\frac{0.232}{0.17} \\ &=1.365[/tex]
The final temperature is determined from the isentropic nozzle efficiency relation:
[tex]T_{2} &=T_{1}-\eta_{N}\left(T_{1}-T_{2 s}\right) \\ &=T_{1}\left(1-\eta_{N}\left(1-\left(\frac{P_{2}}{P_{1}}\right)^{(k-1) / k}\right)\right) \\ &=1400\left(1-0.88\left(1-\left(\frac{800}{100}\right)^{(1.365-1) / 1.365}\right)\right) \mathrm{R} \\ &=969.1 \mathrm{R}[/tex]
b. The outlet velocity is determined from the energy balance:
[tex]h_{1} &+\frac{v_{1}^{2}}{2}=h_{2}+\frac{v_{2}^{2}}{2} \\ v_{2} &=\sqrt{2 c_{p}\left(T_{1}-T_{2}\right)} \\ &=\sqrt{2 \cdot 0.232(1400-969.2) \cdot 25037} \frac{\mathrm{ft}}{\mathrm{s}} \\ &=2237 \frac{\mathrm{ft}}{\mathrm{s}}[/tex]
11. The modern periodic table is arranged in order of increasing atomic
O radius
O charge
O number
O mass
Answer:
number. so the option is c
Answer:
atomic number
Explanation:
i just know it
Which of the following is a period 4 representative element?
A. C
B. An
C. Ti
D. K
[tex]\huge{\mathbb{\tt { QUESTION↓}}}[/tex]
Which of the following is a period 4 representative element?
O A. C
O B. An
O C. Ti
O D. K
[tex]\huge{\mathbb{\tt {ANSWER↓}}}[/tex]
[tex]\color{blue}{\tt {A.C ( Carbon )}}[/tex]
[tex]{\boxed{\boxed{\tt { WHAT \: IS \: CARBON?}}}}[/tex]
Carbon (from Latin: carbo "coal") is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalen - making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust.#CarryOnLearning
#LetsEnjoyTheSummer
→XxKim02xXwhat plate boundary typically causes earthquakes
Answer:
Convergent Plate Boundaries
Explanation:
I hope this helps :)
The dropping off of sediments in a new place is called
What Mass of glucose is
needed to prepare 235mL of 22% w/v glucose?
Answer: 8 grams of glucose are needed to prepare 400. ml of a 2.0%(m/v) glucose solution. 8 grams of glucose are needed to prepare 400.Oct 6, 2017
Answer:
8 grams of glucose are needed to prepare 400. ml of a 2.0%(m/v) glucose solution. 8 grams of glucose are needed to prepare 400
Explanation:
A hydrogen fuel cell is an electrochemical reactor in which oxygen and hydrogen gas are reacted to produce energy. Rather than combusting hydrogen in the presence of oxygen, the overall reaction (1/2) O2 H2 → H2O is actually carried out as two `half-reactions’ occurring at separate electrodes. To complete the reaction, this forces electrons to pass through an external circuit from one electrode to the other, and this current can be used to do work; e.g., by driving a motor. Typical operating conditions for a solid-oxide fuel cell are 500-900 C and 5-15 bar. Consider a fuel cell in which a pure oxygen stream and a pure hydrogen stream enter at 11 bar and 700 C with stoichiometric flowrates. Assume that these reactants are consumed completely, and that the water generated by the reaction leaves in a third stream at the same T and P. Assume that the fuel cell operates at steady-state with a uniform temperature of 700 C. a) Write simplified first and
Answer:
(d) Why is the fuel cell in Question (c) described as an alkaline fuel cell? (e) Another type of fuel cell uses methanol instead of hydrogen.
Explanation:
The first three half live of a chemical 2 / 2 reaction are as follows 44 min, 22 min, 11 min. What is the order the reaction?
6. If 4 grams of salt is dissolved in 79 grams of water, what is the total mass of the final solution? [1 mark]
a) 83g
b)4g
c) 79g
d) 81g
Answer:
A) 83g
Explanation:
Answer:
mass of solution=mass of solute+mass of solvent
=4+79
. =83g
Write an equation and solve the problem.
3. Dexter buys a package of 38 plates. He already
has 4 plates. He puts an equal number on each of
6 tables. How many plates are on each table?
Complete the following sentence by choosing the best answer:
Waves transfer ____.
a. particles
b. energy
с. light
d. matter
Answer: it is b give braineless
Explanation:
William Rankine coined this energy from
A. Mechanical energy
B. Kinetic energy
C. Potential Energy
D. Total energy
E. Chemical Energy
Answer:
C.Potential Energy
Explanation:
To what temperature must a balloon, initially at 25°C and 2.00 L, be heated in order to have a volume of 6.00 L
Answer:
894 deg K
Explanation:
The computation is shown below:
Given that
V1 denotes the initial volume of gas = 2.00 L
T1 denotes the initial temperature of gas = 25 + 273 = 298 K
V2 denotes the final volume of gas = 6.00 L
T2 = ?
Based on the above information
Here we assume that the pressure is remain constant,
So,
V1 ÷ T1 = V2 ÷ T2
T2 = T1 × V2 ÷ V1
= (298)(6) ÷ (2)
= 894 deg K
You have 2.2 mol Xe and 2.1 mol F2, but when you carry out the
reaction you end up with only 0.25 mol XeFg. What is the percent
yield of this experiment?
Xe(g) + 2 F2 (g) XeF, (g)
Answer:
Percentage yield = 23.8%
Explanation:
We'll begin by determining the limiting reactant. This can be obtained as follow:
Xe(g) + 2F₂(g) —> XeF₄
From the balanced equation above,
1 mole of Xe reacted with 2 moles of F₂.
Therefore, 2.2 moles of Xe will react with = 2.2 × 2 = 4.4 moles of F₂.
From the above calculation, we can see that a higher amount (i.e 4.4 moles) of F₂ than what was given (i.e 2.1 moles) is needed to react completely with 2.2 moles Xe.
Therefore, F₂ is the limiting reactant and Xe is the excess reactant.
Next, we shall determine the theoretical yield of XeF₄.
This can be obtained by using the limiting reactant as follow:
From the balanced equation above,
2 moles of F₂ reacted to produce 1 mole of XeF₄.
Therefore, 2.1 moles of F₂ will react to produce = (2.1 × 1)/2 = 1.05 moles of XeF₄.
Thus, the theoretical yield of XeF₄ is 1.05 moles.
Finally, we shall determine the percentage yield. This can be obtained as follow:
Actual yield of XeF₄ = 0.25 mole
Theoretical yield of XeF₄ = 1.05 moles
Percentage yield =?
Percentage yield = Actual yield / Theoretical yield × 100
Percentage yield = 0.25 / 1.05 × 100
Percentage yield = 0.238 × 100
Percentage yield = 23.8%
b) Name three substances which can undergo sublimation and deposition respectively
solid carbon dioxide, iodine, arsenic, and naphthalene
Explanation:
Examples of substances that undergo sublimation
Examples of solids that sublime are dry ice (solid carbon dioxide), iodine, arsenic, and naphthalene (the stuff mothballs are made of).
Aspirin can be prepared from salicylic acid ( C 7 H 6 O 3 CX7HX6OX3), which has a molar mass of 138.12 g/mol, and acetic anhydride ( C 4 H 6 O 3 CX4HX6OX3), which has a molar mass of 102.04 g/mol. The density of acetic anhydride is 1.082 g/mL. C 7 H 6 O 3 + C 4 H 6 O 3 ⟶ C 9 H 8 O 4 + C 2 H 3 O 2 CX7HX6OX3+CX4HX6OX3⟶CX9HX8OX4+CX2HX3OX2 What is the theoretical yield, in grams, of aspirin ( C 9 H 8 O 4 CX9HX8OX4), which has a molar mass of 180.15 g/mol, possible when reacting 3.20 g of salicylic acid with 3.71 mL of acetic anhydride? Type answer:
Answer: The theoretical yield of aspirin is 4.14 g
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex] [tex]\text{Moles of salicylic acid}=\frac{3.20g}{138.12g/mol}=0.023moles[/tex]
mass of acetic anhydride = [tex]density\times volume =1.082g/ml\times 3.71ml=4.01g[/tex]
[tex]\text{Moles of acetic anhydride}=\frac{4.01g}{102.04g/mol}=0.039moles[/tex]
[tex]C_9H_6O_3+C_4H_6O_3\rightarrow C_9H_8O_4+C_2H_3O_2[/tex]
According to stoichiometry :
1 mole of salycylic acid require 1 mole of acetic anhydride
Thus 0.023 moles of salycylic acid require=[tex]\frac{1}{1}\times 0.023=0.023moles[/tex] of acetic anhydride
Thus salycylic acid is the limiting reagent as it limits the formation of product and acetic anhydride is the excess reagent.
As 1 mole of salycylic give = 1 mole of aspirin
Thus 0.023 moles of salycylic acid give =[tex]\frac{1}{1}\times 0.023=0.023moles[/tex] of aspirin
Mass of aspirin = [tex]moles\times {\text {Molar mass}}=0.023moles\times 180.15g/mol=4.14g[/tex]
Thus theoretical yield of aspirin is 4.14 g
What is the volume of 40.0 grams of argon gas at STP ?
Answer:
24.9 L Ar
General Formulas and Concepts:
Atomic Structure
Reading a Periodic TableMolesSTP (Standard Conditions for Temperature and Pressure) = 22.4 L per mole at 1 atm, 273 KAqueous Solutions
States of MatterStoichiometry
Using Dimensional AnalysisExplanation:
Step 1: Define
[Given] 40.0 g Ar
[Solve] L Ar
Step 2: Identify Conversions
[PT] Molar Mass of Ar - 39.95 g/mol
[STP] 22.4 L = 1 mol
Step 3: Convert
[DA] Set up: [tex]\displaystyle 40.0 \ g \ Ar(\frac{1 \ mol \ Ar}{39.95 \ g \ Ar})(\frac{22.4 \ L \ Ar}{1 \ mol \ Ar})[/tex][DA] Divide/Multiply [Cancel out units]: [tex]\displaystyle 24.9235 \ L \ Ar[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
24.9235 L Ar ≈ 24.9 L Ar
Plz help me!!!!plzzz!
Answer:
A
Explanation:
Since the new moon is behind the earth, It is sun, earth, moon
N 2H 4 + H202 N2 + H 20
Answer:
N2 + H20
Explanation:
chemical equation balancer
Draw a mechanism for the reaction of methanol with sodium amide. Draw any necessary curved arrows. Show the products of the reaction. Include any nonzero formal charges and all lone pairs of electrons. Finally, choose one of the options below to indicate which side of the reaction is favored at equilibrium.
a) Reactants favored
b) Products favored
c) Neither side favored
Answer:
Please find equations in the attachment file.
Explanation: