Answer:
28
Explanation:
Which pair of elements would combine to form an ionic compound?
а
b
sodium and calcium
sodium and chlorine
carbon and oxygen
carbon and sulfur
с
d
sodium and chlorine Because Sodium and chlorine make Salt which are ionic compound.
Sarah, Leah, Haley, Lindsay, and Kim bought 4 bottles of water to share among themselves. They divided each bottle of water into 5 equal portions. Sarah took 1 portion from each bottle of water.
Answer:
4/5 of a bottle
Explanation:
Sarah, Leah, Haley, Lindsay, and Kim bought 4 bottles of water to share among themselves. They divided each bottle of water into 5 equal portions. Sarah took 1 portion from each bottle of water. Which equation represents how much of a bottle of water Sarah took?
Sarah must have taken 4/5 of a bottle
First, the 4 bottles of water were divided into 5 equal portions;
4 x 5 = 20 portions.
Sara too 1 portion from each bottle;
1 portion x 4 bottles = 4 portions
Which equation represents how much of a bottle water Sarah took?
Since each bottle water was divided into 5 equal proportions and assuming that the bottle waters are of the same volumes, then Sarah has taken 4 out of 5 portions of a bottle water.
Answer: 4 ÷ 5 ﹦4/5 ♡♡♡
Explanation: When you see eqautions like these, always remember that the first number goes on the top and the second one goes on the bottom. Hope this helps! (~﹃~)~Hi☆
Look at these two molecular diagrams and think about the features of the compounds. (SEE PICTURE)
1. A chain of 5 C atoms is bonded to H above and below and to the left and the right, except that the 4th C is bonded to C H subscript 3 above instead of a plain H. 2. A chain of 4 C atoms is bonded to H above and below and to the left and the right, except the second C in the chain is bonded to C H subscript 3 above and below.
Which descriptions apply to these two compounds? Check all that apply.
are isomers of each other
have same molecular formula
have same structural formula
are both hydrocarbons
have same number of each kind of atom
have same geometric arrangement of atoms
Answer:
A, B, D, E
Explanation:
correct on Edge 2020
Answer:
1) are isomers of each other
2) are isomers of each other
4) are both hydrocarbons
5) have same number of each kind of atom
Explanation: edg 2020
The half-life of gold-198 is 2.7 days. After
amount of gold-198 will remain.
days, 1/4 of the original
Answer: 8.1 days
Explanation:
Expression for rate law for first order kinetics is given by:
[tex]t=\frac{2.303}{k}\log\frac{a}{a-x}[/tex]
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant = x
a - x = amount left after decay process= [tex]\frac{x}{4}[/tex]
a) to find rate constant
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
[tex]t_{\frac{1}{2}}=\frac{0.693}{k}[/tex]
[tex]k=\frac{0.693}{2.7days}=0.257days^{-1}[/tex]
b) for completion of one fourth of reaction
[tex]t=\frac{2.303}{k}\log\frac{x}{\frac{x}{4}}[/tex]
[tex]t=\frac{2.303}{0.257}\log{4}[/tex]
[tex]t=8.1days[/tex]
Thus after 8.1 days , one fourth of original amount will remain.
10) Intravenous saline solutions have a concentration of 1.5 M NaCl. How many liters of saline can be prepared from 50.0 g of NaCl?
Answer:
0.57 mol/L
Explanation:
Molarity (M) is defined as the number of moles of solute per liter of solution (moles/Liter).
Molarity = [tex]\frac{moles of solute}{liters of solution}[/tex] or Moles = molarity × litres
so, the mass of Nacl in 1 mol is 58.44 g,
Moles of NaCl = 50.0g x 1 mole NaCl / 58.44 g
= 0.855 mol NaCl
Moles = molarity × litres
0.855 = 1.5 M x L
L = 0.57 mol/L
Hence, 0.57 mol/L can be prepared from 50.0 g of NaCl.
How is the atmospheric oxygen that is taken in by living things for respiration replaced?
A) After living things use oxygen for respiration, they exhale the oxygen back to the atmosphere.
B) Photosynthesis uses the carbon dioxide that is exhaled by living things to make oxygen.
C) Weathering releases oxygen that is locked in rocks due to sedimentation.
D) Oxygen that is dissolved in water such as oceans is released.
Answer:
B.) Photosynthesis uses the carbon dioxide that is exhaled by living things to make oxygen.
Explanation:
What happens to a neutral atom when an electron leaves
The balloon in this image was rubbed with a piece of wool material. Now, it is negatively charged. What force allows the charged balloon to "pick up" the small pieces of paper off of the table?
The negatively charged balloon is attracted to negative static charges in the paper..
The negatively charged balloon is attracted to the north pole of the paper pieces.
The negatively charged balloon is attracted to the south pole of the paper pieces.
The negatively charged balloon is attracted to the positive static charges in the paper.
What is the best explanation of electric current in a wire?
Electrons build up in the wire and create a charge.
Electrons flow because of electrical attraction and repulsion.
Protons are pushed along by electric forces.
Atoms move because of heat.
Why does the light bulb in a circuit turn on when you close the switch?
The switch absorbs the electrical energy.
The switch changes the direction of the flow of electrons.
Closing the switch completes the circuit, making it a closed circuit.
The switch changes the circuit from series to parallel.
Earth is dipolar, like a bar magnet.
What does this mean about its magnetic poles?
There is only a magnetic south pole.
There is only a magnetic north pole.
There are both magnetic north and south poles.
There are two magnetic north poles.
Which arrangement described below would result in magnetic poles that attract one another?
North Pole + South Pole
South Pole + West Pole
East Pole + North Pole
North Pole + North Pole
Why is an electromagnet a temporary magnet?
An electromagnet only attracts other permanent magnets.
An electromagnet becomes a magnet when a current flows through the wire. An electromagnet no longer acts as a magnet when the current flow stops.
An electromagnet cannot be turned on and off.
An electromagnet is a magnet when no current flows through the wire. The electromagnet no longer acts as a magnet when current flows through the wire.
What set of materials listed below could be used to create a complete electromagnet?
wires and battery
iron nail and battery
iron nail, magnet, and wire
battery, iron nail, copper wire
Where is a bar magnet's magnetic field the strongest?
red part of the magnet
longest part of the magnet
magnetic poles (N + S)
center of the magnet
A(n) ___________ is represented in the diagram it converts electrical energy into mechanical motion.
generator
electromagnet
parallel circuit
motor
Answer:
I actually have no idea
Explanation:
Sorry my man
Answer:
Explanation:
generator
in a titration 20.0 mL of 0.150 M NaOH(aq) Solution exactly neutralize is 24.0 mL of an HCl solution what is the concentration of the HCl solution
Answer:
0.125
Explanation:
i took a test and got it right choosing this answer hopes this help
Cylinder A contains a gas whose molecules have an average speed of 0.0000001 meters/sec. Cylinder B contains a gas whose molecules have an average speed of 0.3 meters/sec. Select the statement below that is true regarding these cylinders. options: Cylinder A contains a gas that has a temperature closest to absolute zero. Even though the molecules are moving at different speeds in the two cylinders, they have the same kinetic energy. Cylinder B contains molecules that are moving more slowly than the molecules in Cylinder A. Cylinder B contains a gas that has a temperature closest to absolute zero.
Answer:
The correct option is;
Cylinder A contains a gas that has a temperature closest to absolute zero
Explanation:
From the kinetic theory of gases, the average speed of a gaseous molecule is found from the following equation;
[tex]v_{rms} = \sqrt{\frac{3\cdot R \cdot T}{MW} }[/tex]
Where:
[tex]v_{rms}[/tex] = rms speed which is the square root of the average of the velocities of the gas molecules squared which is used in place of the average of the gas molecules as the sum of the velocities of all the gas molecules in the cylinder is zero
R = Universal gas constant = 8.3145 J/(mol·K)
MW = Molecular weight of the gas
Hence where we have;
[tex]v_{rmsA}[/tex] = Average velocity of gas A = 0.0000001 m/s
[tex]v_{rmsB}[/tex] = Average velocity of gas B = 0.3 m/s
Since, R and MW are constant for the gas in cylinder A constant, therefore, as [tex]v_{rmsA}[/tex] ≈ 0 m/s, the temperature, [tex]T_A[/tex], of gas A is closest to absolute zero.
what is whether? what is climate? Does todays weather impact climate?
Answer:
Weather is the state in which a certain part inside the atmosphere is hot or cold.Climate is the usual weather in a certain place in the world or atmosphere.One way weather can affect climate is global warming,which is when the world gets hotter and the ice in the world melts and water rises.
Explanation:
climate can be defined as the long-term weather.
People who live in hot, dry climates often rely on _________________________ for their drinking water
Answer:
People who live in hot, dry climates often rely on desalination plants for their drinking water.
Explanation:
This is your answer.
How do American cities now protect their water resources
Answer:
They can use man made materials or they can also have designed areas that people can’t go into
Explanation:
The ___________________ is an early theory which states that our solar system was formed by the gravitational collapse of a massive giant cloud.
A) Nebular Theory
B) Capture Theory
C) Proto-planet Theory
D) Schmidt-Lyttleton accretion theory
Answer: A) Nebular Theory
Explanation:
Answer:
A)
Explanation:
What’s the two products of H2Co3
Answer:
Hydrogen and Cobalt
Explanation:
Break up each individual element
- Hope that helps! Please let me know if you need further explanation.
What volume of 0.125 M HCl is needed to titrate 50.0 mL of 0.0500 M NH3 solution ?
Answer:
20
Explanation:
Discribe how an internal combustion engine works. What is drawback to the type of power?
Answer:
An internal combustion engine is a heat engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. The force of combustion is converted into mechanical energy through the use of levers and gears. The by products of combustion include energy, water vapor, carbon dioxide (CO2), nitric oxide (NO), nitrogen dioxide (NO2), and carbon monoxide (CO). The two primary drawbacks to the internal combustion engine are the primary energy source is non-renewable (fossil fuels) and the by products can have damaging effects on the environment.
Explanation:
please help me please
Answer:
b
Explanation:
i read this once and remember,trust me!
Answer:
20 is b and 21 is a.
PLS HELP
In the balanced equation:
H3PO4(aq) + NH3(aq) ↔ X(aq) + NH4+(aq)
The particle represented by X(aq) is
A) H2PO4–(aq)
B) HPO42–(aq)
C) PO43–(aq)
D) H3PO4(aq)
Answer:
The particle represented by X(aq) is A) H₂PO₄⁻(aq)
Explanation:
According to the Brønsted-Lowry Theory, a base is a substance capable of accepting protons (H⁺) in solution. Conversely, a substance acts as an acid if it acts as a proton donor.
A proton transfer then occurs, requiring the presence of a proton donor (an acid) and a base that accepts them.
When an acid gives up a proton, it becomes an anion, generating a conjugate base. That is, a conjugate base is an ion or molecule resulting from the acid that loses the proton. Conversely, a conjugated acid is an ion or molecule resulting from the base that the proton gains.
In this NH₃ / NH₄⁺ pair that NH₄⁺ is the conjugate acid of the NH₃ base, the latter acting as a base since it accepts a proton. H₃PO₄ then acts as an acid, yielding a proton and generating the conjugate base H₂PO₄⁻.
So, the particle represented by X(aq) is A) H₂PO₄⁻(aq)
Explain the effects that different frequencies of electromagnetic radiation have when absorbed by matter.
As the frequency of the radiation increases further, into the visible light spectrum, it can cause electronic transitions in atoms and molecules, leading to the emission of light and other optical effects.
What is electromagnetic radiation?Electromagnetic radiation is a form of energy that travels through space in the form of waves, without the need for a medium to propagate. It is characterized by oscillating electric and magnetic fields that are perpendicular to each other and the direction of propagation.
At low frequencies, such as radio waves and microwaves, the radiation typically only causes heating of the matter, as it transfers energy to the molecules in the material.
At higher frequencies, such as infrared radiation, the radiation can cause vibrations in the atoms and molecules of matter, leading to heating and thermal effects.
Thus, When matter absorbs electromagnetic radiation, the effects that it has on the matter depend on the frequency of the radiation.
To learn more about the electromagnetic radiation, follow the link:
https://brainly.com/question/10759891
#SPJ3
What is the charge on an electron?
Answer:
The answer is negative .
What is the Big bang Theory
Answer:
The Big Bang Theory is the leading explanation about how the universe began. At its simplest, it says the universe as we know it started with a small singularity, then inflated over the next 13.8 billion years to the cosmos that we know today.
Explanation:
Help Chem asap!!!!! Brainslist
Answer:
OH-
Explanation:
The conditions of 1 atm pressure and 0°C are known as
help me name these molecules please
Answer:
1. carboxylic acid
2. ether
3. ester
4. aldehyde
5. ketone
6. amine
7. alcohol
Explanation:
Know the functional groups. If you would like to learn them, let me know.
- Hope that helps! Please let me know if you need further explanation.
.
A pure gas that is 14.3% hydrogen and 85,7% carbon by mass has a density of 2.5 g L-' at 0°C and 1 atm
pressure. What is the molecular formula of the gas
Answer:
C
Explanation:
4× CH2 = C4H8
Picture of 2010 Todd Abronowitz Gas Laws problems, super fun if you’re in AP chem. Can you help a pre-AP struggling student out please?
Answer:
1. 0.422 atmospheres
2. 633281.25 Pascals
3. (a) Move up
(b) 868 mmHg
4. 868 mmHg
5. 775 mmHg
6. Partial pressure of He is 0.64 atm.
Partial pressure of oxygen is 1.29 atm.
Partial pressure of N is 2.57 atm.
7. 445.72 torr.
Explanation:
1. To convert 321 torr to atmospheres
1 atmosphere = 760 torr
∴ 1 torr = 1/760 atmospheres
Hence, 321 torr = 321 × 1/760 = 321/760 atmospheres = 0.422 atmospheres
2. To convert 6.25 atmospheres to Pascals, we have;
1 atmosphere = 101325 Pascals
∴ 6.25 atmospheres = 6.25 × 101325 Pascals = 633281.25 Pascals
3. (a) Here we have, given that the value of the pressure on the bottle = 830 mmHg, when the valve is opened, the mercury in the open-end arm will move up because the pressure of the gas inside the flask is more than the pressure on the other side of the open-end arm
(b) After the mercury stops moving the difference between the two columns will be the difference between the two pressures, that is 830 mmHg - 745 mmHg = 85 mmHg
4. From the diagram, it is seen that the differenc beteen the two columns is 123 mm, therefore, the pressure in the flask is 123 mmHg more than the external pressure, hence the pressure of the as in the flask = 745 mmHg + 123 mmHg = 868 mmHg
5. Here we have that the height of the mercury in the open-end is less than the height of the mercury on the arm closer to the flask, therefore, the pressure of the gas in the flask = 825 mmHg - 50 mmHg = 775 mmHg
6. Number of moles of He = 1 mole
Number of moles of oxygen, O = 2 mole
Number of moles of nitrogen, N = 4 mole
From Dalton's law of partial pressure we have that, the total pressure of a given mass of gas is equal to the partial pressure of the individual gases
[tex]That \ is \ \chi _i = \frac{n_i}{n_{total}} \ and \ P_i = \chi_i \cdot P_{total}[/tex]
Hence;
Total number of moles = 1 + 2 + 4 = 7 moles
Mole fraction of He = 1/7
Partial pressure of He = 1/7×4.5 = 0.64 atm.
Mole fraction of oxygen, O = 2/7
Partial pressure of oxygen= 2/7×4.5 = 1.29 atm.
Mole fraction of N = 4/7
Partial pressure of N = 4/7×4.5 = 2.57 atm.
7. From Boyle's law
P₁×V₁ = P₂×V₂
Hence;
P₂ = P₁×V₁/V₂
Where:
P₁ = Initial pressure = 2.57 atm
V₁ = Initial volume =1.57 liters
V₂ = New volume = 6.88 liters
P₂ = New pressure = 2.57×1.57/6.88 = 0.59 atm.
To convert 0.59 atm. to torr, we multiply by 760 thus;
0.59 atm. = 0.59 × 760 torr = 445.72 torr.
Which of the following are social implications of an environmental policy? Check all that apply.
loss of jobs
poorer air quality
less erosion
cleaner water waste
higher taxes
elimination of tourist activities
Answer:
the correct answer is lost of jobs,higher taxes, and elimination of tourist activities
Explanation:
hope you have a blessed day:)
Answer:
the correct answer is lost of jobs,higher taxes, and elimination of tourist activities
Explanation:
thank you for the answer i hope EVERYONE has A BLESSED DAY!!!!!!!!!!!!!!!!!!!!!!
Identify three details for how the Earth and Moon are different
State duplet rule .