Answer:
A transition element atomic number 29 copper Cu
Explanation:
the boiling point of isopropyl alcohol is 82.5°C. a student conducts an experiment and finds a boiling point of 83.1°C. what is the students percent error in this experiment?
A.0.6%
B. 0.7%
C. 1.0%
D. 99.3%
Answer:
B. 0.7%
Explanation:
Given data:
Actual boiling point = 82.5°C
Experimental boiling point = 83.1°C
Percent error = ?
Solution:
Formula:
Percent error = ( actual value - experimental value / actual value )×100
by putting values,
Percent error = (82.5°C - 83.1 °C /82.5°C) × 100
Percent error = 0.007 × 100
Percent error = 0.7 %
Negative sign shows that experimental value is greater than accepted value. It can not written in result.
For the cold pack shown below, the temperature on the outside surface has dropped considerably from its initial temperature of 25 °C. Which of the following provides the best explanation for this temperature decrease?
Answer:
The correct answer is D
Explanation:
In an endothermic process, energy travels from the surroundings into the system. The decrease in the temperature on the outside of the bag indicates that energy has moved from the surroundings into the system.
The other answers are incorrect. A bag cannot release “cold” into the surroundings since cold refers to the absence of heat. The surroundings become colder when heat is removed. Option B is incorrect because the cooling is due to the cold pack absorbing heat energy from its surroundings. Option C is incorrect because a cold pack absorbs heat energy from the surroundings, not vice versa.
The surroundings are losing energy and the thermometer is measuring the temperature of the surroundings as the cold pack shows an endothermic process. Therefore, Option (D) is correct.
What is an endothermic reaction?Endothermic reactions are those in which the reactants absorb heat energy from their surroundings to form products. Endothermic reactions reduce the temperature of their surroundings and create a cooling effect. Physical processes can be endothermic in nature as well, for example, ice cubes absorb heat from their surroundings to form liquid water.
Endothermic reactions include the making of chemical bonds through the absorption of energy from the surroundings. On the other hand, exothermic reactions are in which the liberation of heat energy is generated from bond breakage.
The temperature of the cold pack is lower than the temperature of the surroundings. So the heat energy will be traveled from the surroundings to the cold pack.
Therefore, the temperature of the surroundings will fall as heat transfers to the cold pack.
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does something that is hot have more thermal energy than something that’s cold?
Answer:
Yes it does because the atoms/molecules are moving faster than they are in a cold substance.
Explanation:
7 Ba(ClO3)2
How many oxygen atoms are shown?
GUYSS JUST ONE QUESTION PLEASE HELPPP!!!!!!
Explanation:
done
..................
Two important ways that energy is transported in the world around us is through
Explanation:
The two ways that energy can be transferred are by doing work and by heat transfer.
what evidence is there of energy release after chemical reaction
Answer:
loss of mass
Explanation:
your welcome :)
which term refers to the condition that exists when no over all change in concentration results from diffusion?
a. concentration
b. osmosis
c. equilibrium
d. randomness
Answer:
a.cocentration es la respuesta
If you knew the number of valence electrons in a nonmetal atom how would you determine the valence of the element. (Ignore hydrogen)
Answer:
The possible valances can be determined by electron configuration and electron negativity
Good Luck even though this was asked 2 weeks ago
Explanation:
All atoms strive for stability. The optima electron configuration is the electron configuration of the VIII A family or inert gases.
Look at the electron configuration of the nonmetal and how many more electrons the nonmetal needs to achieve the stable electron configuration of the inert gases. Non metals tend to be negative in nature and gain electrons. ( They are oxidizing agents)
For example Florine atomic number 9 needs one more electron to reach a valance number of 8 electrons to equal Neon atomic number 10. Hence Flowrine has a valance of -1
Oxygen atomic number 8 needs two more electrons to reach a valance number of 8 electrons to equal Neon atomic number 10. Hence Oxygen has a valance charge of -2.
Non metals with a low electron negativity will lose electrons when reacting with another non metal that has a higher electron negativity. When the non metal forms an ion it is necessary to look at the electron structure to determine how many electrons the element can lose to gain stability.
For example Chlorine which is normally -1 like Florine when it combines with oxygen can be +1, +3, + 5 or +7. It can lose its one unpaired electron, or combinations of the unpaired electron and sets of the three pairs of electrons.
I'd love some help please thank you
Answer:
the answer would be B
Explanation:
The move vigorously it is the higher the reactivity so if you put it in order the answer would be B
what is an example of a chemical change that occurs during weathering
Answer:
Hydrolysis is a chemical wheathering process that may affect silicates and carbonates minerals. an example of such a reaction in which water reacts with a silicates minerals is the following: Mg2SiO4 + 4H2O ⇄ 2 Mg(OH)2 + H4SiO. olivine (forsterite) + water ⇄ brucite + silicic acid.
Explanation:
How does Cyanoacrylate compare to the elements that make it up?
Answer: The elements of the cyanoacrylate are different as compared to the main cyanoacrylate.
Explanation:
The cyanoacrylate is a adhesive water based substance. It is used for developing fingerprints by fuming method. It is the acrylic monomer which has property to develop into a plastic form after application another of its composition is the acrylic resin which imparts adhesiveness to the cyanoacrylate.
A gas with a volume of 2 L at 25°C is placed into a container that is 4 L. What is the new temperature of the gas?
Given :
A gas with a volume of 2 L at 25°C is placed into a container that is 4 L.
To Find :
The new temperature of the gas.
Solution :
Since, their is no information regarding pressure. We will assume that pressure is constant.
Now, we know when at constant pressure, volume is directly proportional to volume.
[tex]\dfrac{V_1}{V_2}=\dfrac{T_1}{T_2}\\\\\dfrac{2}{4} = \dfrac{25 + 273 }{x}\\\\x = 2 \times ( 25 + 273 )\\\\x = 596\ K[/tex]
Therefore, the new temperature of the gas is 596 - 273 K = 323 K.
When can I use ideal gas law?
1. List the types of fronts found on this map
Answer:
Cold Front. A side view of a cold front (A, top) and how it is represented on a weather map (B, bottom). ...
Warm Front. ...
Stationary Front. ...
Occluded Front.
Wass, volume and density are all properties of
matter
3
weight.
formula
Answer:
:)
Explanation:
They are all properties of Matter. weight and formula wouldn't make sense.
PLEASE ANSWER QUICK! 50 POINTS!!!!
How does the structure of amino acids allow them to form a polypeptide?
Options:
A. Each amino acid has an amino group and a carboxyl group.
B. Each amino acid has a hydrogen atom and a carboxyl group.
C. Each amino acid has a carboxyl group and an R group.
D. Each amino acid has an R group and a hydrogen atom.
Answer:
A. Each amino acid has an amino group and a carboxyl group.
Answer:a
Explanation:
Please help and I will give brainliest!
I am going to put them in order
R r
R RR rR
r rR rr
3. A 240 mL sample of argon gas at 270 K is cooled until the volume is 180 mL. What is the new temperature?
Answer:
202.5 K
Explanation:
What did most of the particles that Rutherford shot at the gold foil do? What was the surprising behavior of a few of the particles? What did he determine?
Answer:
Explanation:
Rutherford gold experiment gave the explanation to some observations made on atoms.
When he shot the gold foil, most of the [tex]\alpha[/tex]-particles passes through the foil undeflected nor absorbed. This faction of the particles propagated the foil as if there was nothing placed on their path.
The surprising behavior of a few of the [tex]\alpha[/tex]-particles was that they were deflected from their initial path on hitting the gold foil.
This implies that there is a part of the gold foil which has the same charge as the [tex]\alpha[/tex]-particles, and more massive than the particles. Thus, he was able to determine the nucleus of an atom.
A 0.200 M NaOH solution was used to titrate a 18.25 mL HE
solution. The endpoint was reached after 31.20 mL of titrant
were added. Find the molar concentration of the original HF
solution.
Answer:
M₂ = 0.34 M
Explanation:
Given data:
Molarity of NaOH =M₁ = 0.200 M
Volume of HF =V₂= 18.25 mL
Volume of NaOH added = V₁ = 31.20 mL
Molarity of HF solution = M₂ = ?
Solution:
M₁V₁ = M₂V₂
by putting values,
0.200 M × 31.20 mL = M₂ × 18.25 mL
M₂ = 0.200 M × 31.20 mL / 18.25 mL
M₂ = 6.24 M.mL / 18.25 mL
M₂ = 0.34 M
What happen when? sodium oxide reacts with HCL
Answer:
Sodium oxide reacts exothermically with cold water to produce sodium hydroxide solution. A concentrated solution of sodium oxide in water will have pH 14. ... For example, it reacts with dilute hydrochloric acid to produce sodium chloride solution.
12. Draw the lewis structure for the element to help you answer the question *
Answer:hope it helps
Explanation:
Question 10
1 pts
Which of the following statements is true about the mass of an atom?
The mass is equal to the neutrons plus the valance electrons
The mass of an atom is equal to the protons plus the neutrons
O The mass is equal to the protons plus the electrons
The mass is equal to the mass of the protons plus the valence electrons
+ Previous
Next >
Answer:
The mass of an atom is equal to the protons plus the neutrons
need help with physical changes
Answer:
I give u three in explanation
Explanation:
Crushing the can, stomping on the can, and squishing the can
Explain Joule's law in your own words. pls help
Answer:
Joules first law is a law that expresses the relatioship between heat that is generated and the current flowing heat thats through a conductor. The second law says that internal energy is independent of volume and pressure, depending only on temperature!
Explanation:
If an 85.0 mL container of helium gas at standard pressure is heated from 20.oC to 91oC and the pressure is increased to 2.8 atm, then what would the new volume be for the He gas
Answer: V₂ = 37.71mL
Explanation: To determine the new volume of Helium gas, use the Combined Gas Law, which states the following relationship among pressure, volume and temperature:
[tex]\frac{P_{1}V_{1}}{T_{1}} =\frac{P_{2}V_{2}}{T_{2}}[/tex]
where index 1 relates to the initial state of the gas and index 2 to the final state of the gas.
Temperature is in Kelvin, so:
T = °C + 273
For this situation, standard pressure is 1 atm. Temperatures will be:
T₁ = 20 + 273 = 293 K
T₂ = 91 + 273 = 364 K
Solving:
[tex]V_{2}=\frac{T_{2}P_{1}V_{1}}{P_{2}T_{1}}[/tex]
[tex]V_{2}=\frac{364*1*85}{2.8*293}[/tex]
[tex]V_{2}=\frac{30940}{820.4}[/tex]
[tex]V_{2}=[/tex] 37.71
The new volume of He gas is 37.71 mL.
Dry ice changes from a solid to a gas in a process known as A. Melting B. Freezing C.sublimation
Answer:
c
Explanation:
solid to gas directly
Magnetic Quantum Number tells you what? how many orbitals are in s, p ,d?
I JUST NEED HELP!!!! ASAP!!!!
Hydrogen cyanide has the chemical formula HCN. What's the formal charge on the N atom?
A)
+2
B)
0
C)
–2
D)
–1
Answer:
Formal charge = valance electron - nonbonding electron - (1/2)bonded electron
For nitrogen atom,
Formal charge = 5 - 2 - (1/2)×6
= 5-2-3
= 0
So, the formal charge on nitrogen atom in HCN is "0".
Explanation:
The formal charge on the N atom of hydrogen cyanide, HCN molecule is 0. Option B is correct.
Formal charge is defined as the individual charge of an atom. It is represented as:
Formal charge = valance electron - nonbonding electron - (1/2)bonded electron
The valence electrons in nitrogen atom is 5, there are 2 non bonding electrons and 6 bonded electrons on N atom in HCN,
Thus, For Hydrogen cyanide molecule, the formal charge on nitrogen atom is calculated as:
Formal charge
= 5 - 2 - (1/2)×6
= 5-2-3
= 0
So, the formal charge on nitrogen atom in HCN is "0".
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