Answer:
A water molecule displays polarity by having negative and positive ends. Due to this charge difference, a water molecule is called a dipole.
Explanation:
b) A piece of solid gold was heated from 274K to 314K using 55.7J of energy to raise the
temperature. What mass of gold was present?
Answer:
Explanation:
So we know q = mc[tex]\Delta[/tex]T.
q = 55.7 J
c = 0.129j/g°C
and [tex]\Delta[/tex]T = 314-274 = 40°C.
and m is mass which can solve since we got every other variable. We will get m = 10.8g.
3. Convert the word equations below to symbolic:
Sodium + chlorine sodium chloride
• Calcium + bromine ---- calcium bromide
• Potassium + water → potassium hydroxide + hydrogen
ot
Answer:
1)2Na + Cl2 ----> 2NaCl
2)Ca + Br2 ---->CaBr2
3)K + H2O -----> KOH + H2
How many atoms are in 57.5 liters of xenon gas at STP
Answer:
1.55 × 10²⁴ atoms Xe
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 K Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisExplanation:
Step 1: Define
[Given] 57.5 L Xe at STP
[Solve] atoms Xe
Step 2: Identify Conversions
[STP] 22.4 L = 1 mol
Avogadro's Number
Step 3: Convert
[DA] Set up: [tex]\displaystyle 57.5 \ L \ Xe(\frac{1 \ mol \ Xe}{22.4 \ L \ Xe})(\frac{6.022 \cdot 10^{23} \ atoms \ Xe}{1 \ mol \ Xe})[/tex][DA] Divide/Multiply [Cancel out units]: [tex]\displaystyle 1.54583 \cdot 10^{24} \ atoms \ Xe[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
1.54583 × 10²⁴ atoms Xe ≈ 1.55 × 10²⁴ atoms Xe
What is the phase label on HCl?
A. g
B. aq
C.
D. e
E. s
Answer:
B. aq if the reaction is inorganic (double or single displacement), neutralization, etc.
Explanation:
Hello there!
In this case, unfortunately we are not given the undergoing chemical reaction; however, in the most of the double displacement, neutralization, precipitation and in general, inorganic reactions, the hydrochloric acid must be B. aq as it must be dissolved in water as the reaction media. On the other hand, in some organic reactions, it can be either aqueous or gaseous, the latter, specially as a product. For that reason, you will need to make sure whether your reaction is organic or inorganic to correctly figure out the phase label.
Best regards!
How long did it take to get the Hubble Telescope into space?
10. Which of the following group of colors of the visible light is listed from
lowest to highest frequency?
A. Blue, green, red
C. Red, violet, green
B. Green, blue, red
D. Red, green, violet
Answer:
The correct answer is - D. Red, green, violet.
Explanation:
Visible light is the spectrum of light that can be seen by the naked eyes of humans without any equipment. This spectrum has various frequency light that helps us see things in color. The frequency of light ranges between seven different colors in which violet has the highest frequency and red has the lowest.
The different frequencies are as follows:
color frequency
red (limit) 1.77
red 1.91
orange 2.06
yellow 2.14
green 2.25
cyan 2.48
blue 2.75
violet (limit) 3.10
On this basis of this the group of colors of the visible light is listed from
lowest to the highest frequency - Red, green, violet
water and Air are needed for iron rust answer true or false
Answer:True
Explanation:
PLZ GIVE ME BRAINLIEST, I NEED IT
Why are diamonds unevenly distributed on Earth?
Soil forms only in places where rock particles are deposited.
Soil forms only in places where larger rocks are broken into smaller rocks.
Soil forms only within the Earth under heavy pressure.
Soil forms in the air and is then deposited mainly in places that get a lot of rain.
Answer:
Why aren't diamonds found evenly distributed on Earth? Diamonds are only formed under specific conditions that involve geological processes, such as volcanic activities and plate movements. Since these conditions and processes only take place in certain areas, you can only find diamonds in these special places.
Explanation:
Explain the difference between an exothermic and an endothermic reaction.
Answer:
Explanation:
Heat is a reactant.
If the equation requires heat to occur, the reaction is endothermic
The equation would have this model
A + B + heat =====> C + D
If the equation gives away heat, then it is exothermic
The equation would look like this. (I'll use a common reaction)
CH4 + 2O2 - heat ===> CO2 + 2H2O
The heat is minus when it has to be given away.
Match each definition to the appropriate term.
Sum of the internal energy plus the product of the pressure and volume for a reaction
The extent of randomness in a system
The condition that a reaction takes place without outside help
Difference of the enthalpy (of a system) minus the product of the entropy and absolute temperature
Solution in which no more solute can be dissolved in the solvent
Answer:
Enthalpy, Entropy, Spontaneity, Gibbs free energy, saturated solution
Explanation:
Enthalpy is defined as the heat released or the heat absorbed during the process at a constant pressure which is equal to the Enthalpy shift. Enthalpy is also called as heat content and it is the sum total of internal energy and the product of the volume and pressure of a system.
Entropy is defined as the measure of randomness of a system or the disorder of the system.
Spontaneity is defined as the condition of being spontaneous. It is the condition where a reaction takes place without any help from outside.
Gibbs free energy is defined as the energy that is used to quantify the maximum work done in a thermodynamic system at constant temperature and pressure. It is the also known as the Gibbs energy or function.
Saturated solution is defined as the solution where the maximum amount of the dissolved solute is present in the solvent. In case of a saturated solution, the extra solute does not dissolve. In order words, it is a solution where no more solute can dissolved in solvent.
The sum of the internal energy plus the product of the pressure and volume for a reaction represents Enthalpy , Entropy is the extent of randomness in a system, Spontaneity is that condition that a reaction takes place without outside help, Gibb's free energy is the difference of the enthalpy (of a system) minus the product of the entropy and absolute temperature and Saturated solution in which no more solute can be dissolved in the solvent.
Which properties will define chemical reaction?Thermodynamically chemical reactions will be define by considering the properties like entropy, enthalpy, free energy, internal energy, temperature and many more.
Enthalpy of the reaction tells about the total amount of heat released or absorbed during a chemical reaction, and it is calculated as sum of the internal energy plus the product of the pressure and volume for a reaction.Entropy of any reaction tells about the randomness and uncertainty present within the molecule or atoms.Spontaneity of any chemical reaction tells about the ease of completion of that reaction. Gibb's free energy is the total energy involved in that reaction and represented as difference of the enthalpy (of a system) minus the product of the entropy and absolute temperature.Saturated solutions are those solutions in which all solute get completely dissolved, no solute will remain undissolved.Hence correct answers are Enthalpy , Entropy ,Spontaneity, Gibb's free energy and Saturated solutions.
To know more about saturated solutions, visit the below link:
https://brainly.com/question/4529762
Coal, oil, and natural gas are called _______.
A.
fossil fuels
B.
renewable resources
C.
nuclear power
D.
solar energy
Answer:
I think it's A. I'm pretty sure.
Explanation:
Answer:
Coal, oil and natural gas are called _________A. fossil fuels
Humans are always consumers. Most humans are omnivores, but some
humans eat only plant matter making them herbivores. However, all
humans are considered to be -
Select one:
autotrophs
heterotrophs
producers
carnivores
Answer:
A. Autotrophs
Explanation:
an autotroph, def an organism that is able to form nutritional organic substances from simple inorganic substances such as carbon dioxide.
humans and other mammals, plants, and a select few other things
Suggest a possible
reason for the change
in sulfur dioxide levels
in North America and
Europe around
1970-1980.
Answer: a reason for this is fossil fuels
Explanation:
The reduction in SO2 is largely due to the implementation of the Acid Rain Program under the Clean Air Act through a cap and trade program for fossil-fuel powered plants.
Help (also tell me what the phenotype and genotypes are)
Answer:
genotype are the organism's hereditary information for example DNA
phenotype are the organism's physical characteristics for example your eyes or hair
or how your nose looks
Identify the term that matches each electrochemistry definition.
a. The electrode where reduction occurs ___________
b. An electrochemical cell powered by a spontaneous redox reaction ___________
c. The electrode where oxidation occurs__________
d. An electrochemical cell that takes in energy to carry out a nonspontaneous redox reaction ____________
e. A chemical equation showing either oxidation or reduction ___________
Answer: a. Cathode
b. Galvanic cell
c. Anode
d. Electrolytic cell
e. half reaction
Explanation:
Galvanic cell or Electrochemical cell is defined as a device which is used for the conversion of the chemical energy produced in a spontaneous redox reaction into the electrical energy.
Electrolytic cell is a device where electrical energy is used to drive a non spontaneous chemical reaction.
In the electrochemical cell, the oxidation occurs at an anode which is a negative electrode and the reduction occurs at the cathode which is a positive electrode. Thus the electrons are produced at anode and travel towards cathode.
The balanced two-half reactions will be:
Oxidation half reaction : [tex]M\rightarrow M^{n+}+ne^-[/tex]
Reduction half reaction : [tex]N^{n+}+ne^-\rightarrow N[/tex]
Thus the overall reaction will be: [tex]M+N^{n+}\rghtarrow M^{n+}+N[/tex]
Which of the following is a primary source for scientific information? O A. Doctoral theses OB. A handbook of scientific facts O C. Reviews of scientific studies D. Public opinion about a scientific issue
Chrysanthemic acid occurs as a mixture of esters in flowers of the chrysanthemum (pyrethrum) family.
a. True
b. False
Answer:
A: True
Explanation:
Statement is true because chrysanthemic acid is formed naturally as a result of production of two molecules of dimethylallyl diphosphate which forms pyrophosphate ester.
Thus, it belongs to the pyrethrum family
What was the purpose of letting the transformed cells sit in LB for a few minutes before spreading them onto the plates?
A. This allows time for the cells to express the antibiotic resistance gene
B. This allows the cells to take up the plasmid after the heat shock procedure
C. This allows time for the cells to warm up before plating
D. This allows cells time to start glowing green
Answer: D
Explanation:
If 4.50 moles of C2H6 undergoes combustion, how many moles of oxygen would it combust with?
Answer:
First balance the equation
C2H6 + 7/2O2 2CO2 +3H2O
for one mole of C2H6 there are 7/2 mole of O2 required. so for4.50 moles you require 4.50 x 7/2 = 15.75 moles of O2.
Explanation:
Due today! Why is it a good idea to have floating cities?
A: We are running out of land
B: We need it for pollution cleanup
C: Oceans are rising
D: It's a sustainable way to live
Answer:
in my opinion I think the answer the be "A"
Gelatinization happens with what type of Carbohydrate?
What is the formal charge on the phosphorus in the PO43- polyatomic ion?
Answer:
P has a formal charge of 0
Explanation:
Essentially P is in the middle of that ion, and its valence electrons are being used with the 4 Os. Hope that makes sense or helps at least. There's good videos that talk about how this works but I can't link them in brainly
Which of the following patients should be admitted as an inpatient at a
hospital?
A. Katie's having her tonsils removed and will be able to go home
shortly after she wakes up from surgery.
B. Phil's having his blood sugar tested and having his annual
physical
c. Salvatore's having a hip transplant and will need to be closely
monitored for a week.
D. Chen's having chest X-rays taken to determine if he has a broken
rib.
SUBMIT
What is the vapor pressure of an aqueous solution that has a solute mole fraction of 0.1000? The vapor pressure of water is 25.756 mmHg at 25 °C.
Answer:
χsolvent = 1.0000 - 0.1000 = 0.9000
Use Raoult's Law:
Psolution = (χsolvent) (P°solvent)
x = (0.900) (25.756)
x = 23.18 mmHg (to four sig figs)
The vapor pressure of an aqueous solution is x = 23.18 mmHg (to four sig figs)
χsolvent = 1.0000 - 0.1000 = 0.9000
Use Raoult's Law:
P solution = (χsolvent) (P°solvent)
x = (0.900) (25.756)
x = 23.18 mmHg (to four sig figs)
What is an aqueous solution?An aqueous answer is one in which the solvent is liquid water. that is, solute (dissolved) ions and molecules are surrounded by water molecules and integrated into the network of bonds within the water. The dissolved species then spread in the course of the water.
A solution wherein water is the solvent is called an aqueous solution. although water is an exceptional solvent, now not the whole thing dissolves comfortably in the water.
Aqueous' in a chemical equation suggests that the cloth dispersed in water (an answer in water). As an example, when we pour sodium hydroxide answer into dilute hydrochloric acid, we get an aqueous solution of sodium chloride. The liquid is used to signify the formation of liquid materials in response.
Learn more about the aqueous solution here: https://brainly.com/question/19587902
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lave
Use the drop-down menus to identify the parts of a
wave.
A
B:
C
D
Answer:
Use the drop-down menus to make your selections.
What is the difference between wave A and wave B?
✔ Wave A has higher amplitude than wave B.
What is the difference between wave C and wave D?
✔ Wave C has a lower frequency than wave D.
Explanation:
Only animals and not plants can adapt to their environment true or false
Answer:
true
Explanation:
np have a good day brainliest?
The nature particle model of matter describe the property of solid, liquid and gas in molecular level. Which of the given statements below is TRUE?
A. Matter is made up of large particles.
B. Particles of matter have spaces between them.
C. Particles of matter are not moving all the time.
D. The particles of matter do not attract each other.
Answer:
B. Particles of matter have spaces between them.
Explanation:
The particle nature model of matter is an model used to explain the properties and nature of matter. The statements of the particle nature model of matter are as follows :
1. Matter is made of small particles of atoms or molecules.
2. The particles of matter have space between them. The spaces between the particles are least in solids as they are closely packed together but are greatest in gases whose particles are far apart from each other.
3. The particles of matter are in constant motion at all times. Solids particles are not free to move due to strong molecular forces between the particles, but are constantly vibrating in their mean positions. Liquid particles free to move due to lesser molecular forces while gas molecules which have negligible intermolecular forces have the greatest ability to move.
4. The particles of matter are attracted to each other by intermolecular forces. These forces are greatest in solids and least in gases.
The correct option is B.
The most common experimental technique to perform elemental analysis is combustion analysis, where a sample is burned in a large excess of oxygen and the combustion products are trapped in a variety of ways. A 99.99% pure, 0.4808 g sample containing only carbon, hydrogen, and nitrogen is subjected to combustion analysis, resulting in the formation of 0.6859 g CO2, 0.6973 g H2O, and 0.4646 g NO. What is the empirical formula of the sample
Answer:
C₂H₅N₂
Explanation:
In the combustion analysis, all NO comes from the nitrogen of the sample, that means:
Moles NO = Moles N in the sample
In the same way:
Moles CO2 = Moles C in the sample
Moles H2O = 1/2 moles H in the sample
To solve this problem we must convert the mass of each gas to moles in order to find the moles of each atom. The empirical formula is the simplest whole number ratio of atoms presents in the molecule:
Moles NO = N -Molar mass: 30g/mol
0.4646g * (1mol / 30g) = 0.01549 moles N
Moles CO2 = C -Molar mass: 44.01g/mol-
0.6859g * (1mol / 44.01g) = 0.01559 moles C
Moles H2O = 1/2moles H -Molar mass: 18.02g/mol-
0.6973g * (1mol / 18.02g) = 0.03870 moles H
The ratio of atoms is -Dividing in the low number of moles = moles N-:
C = 0.01559 / 0.01549 = 1
N = 0.01549 / 0.01549 = 1
H = 0.03870 / 0.01549 = 2.5
Twice this ratio of atoms -Because empirical formula must be given only with whole numbers:
C = 2
N = 2
H = 5
The empirical formula is:
C₂H₅N₂Part A
How many moles of chlorine gas are needed to make 0.6 moles of sodium chloride?
Given the reaction: 2Na + Cl2 + 2NaCl
O 1.2
O 0.6
0 3.6
O 0.3
not enough information
Submit
Request Answer
Answer:
[tex]n_{Cl_2}=0.3molCl_2[/tex]
Explanation:
Hello there!
In this case, according to the given chemical reaction whereas the sodium chloride is in a 2:1 mole ratio with chlorine, the required moles of the later are computed as shown below:
[tex]n_{Cl_2}=0.6molNaCl*\frac{1molCl_2}{2molNaCl}[/tex]
So we cancel out the moles of NaCl to obtain:
[tex]n_{Cl_2}=0.3molCl_2[/tex]
Best regards!
12. How many moles of atoms are present in 154 g of Na2O?
A) 2.48 mol
B) 7.45 mol
C) 51.3 mol
D) 0.827 mol
Answer:
[tex]\boxed {\boxed {\sf A. \ 2.48 \ mol \ Na_2O}}[/tex]
Explanation:
We are asked to convert an amount in grams to moles. To do this, we use the molar mass. This is the number of grams in one mole of a substance. It is the same value numerically as the atomic mass on the Periodic Table, however the units are grams per mole, not atomic mass units.
Look up the molar masses for the individual elements.
Sodium (Na): 22.9897693 g/mol Oxygen (O): 15.999 g/molLook back at the formula: Na₂O. Notice there is a subscript of 2 after sodium. This means there are 2 atoms of sodium in every molecule, so we have to multiply sodium's molar mass by 2 before adding oxygen's.
Na₂O: 2(22.9897693 g/mol)+ 15.999 g/mol = 61.9785386 g/molSet up a ratio using the molar mass.
[tex]\frac {61.9785386 \ g \ Na_2O}{1 \ mol \ Na_2O}[/tex]
Multiply by the given number of grams.
[tex]154 \ g \ Na_2O*\frac {61.9785386 \ g \ Na_2O}{1 \ mol \ Na_2O}[/tex]
Flip the ratio so the grams of sodium oxide can cancel each other out.
[tex]154 \ g \ Na_2O*\frac {1 \ mol \ Na_2O}{61.9785386 \ g \ Na_2O}[/tex]
[tex]154 *\frac {1 \ mol \ Na_2O}{61.9785386 }[/tex]
[tex]\frac {154}{61.9785386 } \ mol \ Na_2O[/tex]
[tex]2.48473106141 \ mol \ Na_2O[/tex]
The original measurement of grams given has 3 significant figures, so our answer must have the same. For the number we calculated, that is the hundredth place.
2.48473106141The 4 in the thousandth place tells us to leave the 8.
[tex]2.48 \ mol \ Na_2O[/tex]
There are 2.48 moles of sodium oxide in 154 grams, so choice A is correct.