Answer:
D . Na
Explanation:
What is the correct shape and polarity of a water molecule
Answer:
D
Explanation:
because both H's should be positive and O is supposed to be negative.
How many molecules are there in 4.3 moles of calcium sulphate ?
Answer:
The law companies that value excessive ethics comply with the legal guidelines not solely in letter however go past what is stipulated 1 My proudest accomplishment is organizing a donation pressure aimed at helping the less fortunate humans skills
Explanation:
My bedroom is very clean and big closest it color
Which states have no oil or gas production?
Answer:
Georgia and minessota
Explanation:
they have no production
How many moles are 9.9 * 1024 molecules of methane?
The nucleus of an atom stays together only because the repulsive forces, called
forces, are overcome by
even stronger attractive forces.
fusion
nuclear
electrostatic
Answer:
Electrostatic
Explanation:
The forces that are overcome are the repulsive electrostatic forces between the protons (all charged positively).
All forms of energy can be traced back to
PLZZZZ HELPP NOWW!!
According to the law of conservation of mass, what is the mass of water
formed in this reaction?
H2
+
02
32.00 g
2H20
?
2.02 g
A. 36.04 grams
B. 55.92 grams
C. 72.08 grams
D. 27.96 grams
Answer:
The law of conservation of mass states that mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations.
According to the law of conservation of mass, the mass of the products in a chemical reaction must equal the mass of the reactants.
The law of conservation of mass is useful for a number of calculations and can be used to solve for unknown masses, such the amount of gas consumed or produced during a reaction.
Answer:
A. 36.04 grams
Explanation:
A.P.E.X
What % of original U238 remains after three half lives?
1-50
2-25
3-12.5
4-6.25
Answer:
12.5
Explanation:
After three half-lives, one eighth (1/2 x 1/2 x 1/2) of the uranium-238 will remain. One-eighth equals 12.5%
What is the concentration of a 22.35 L solution that contains 9.95 moles of sodium
acetate? Round your answer to the correct number of significant figures.
Answer:
0.445 M
Explanation:
Molarity = moles/Volume
M = 9.95/22.35 = 0.445 M
Which of these statements best supports the idea that a cell is the basic unit of a living organism?
A.
The number of cells in an organism affects the size of that organism.
B.
A tissue is composed of cells with similar structure and function.
C.
Some organisms have only one cell.
D.
All organisms are made up of one or more cells.
Answer:
The answer is D.
Explanation:
I searched it up :)
How many grams of a 26.9% sugar solution contain 49.0 g of sugar?
Answer:
182.156g
Explanation:
grams = 49/.269 = 182.156g needed
What is the mass of 500 trillion (5.0 x 10'4)
molecules of water?
What is the enthalpy change(Q) when 60.0 g of NaOH is dissolved in one litre of water, given that the temperature of the solution increased by 15.8 °C?
Answer:
ΔH = -44.029 KJ/mol
Explanation:
We are told that 60.0 g of NaOH is dissolved in one litre of water.
From conversion, 1 litre = 1000 g
From tables, specific heat capacity of water; c = 4.18 J/g/°C
We are given ΔT = 15.8 °C
Formula for the heat absorbed by the solution is given as;
Q = mcΔT
Where;
Q = Heat gained by the water
m = Mass of the water
c = Specific heat of water
ΔT = change in temperature
Thus;
Q = 1000 × 4.18 × 15.8
Q = 66044 J
The solution absorbed 66044 J and therefore it means that the dissolution of the salt gave off 66044 J.
Thus;
Enthalpy is; ΔH = -66044 J
Now, Mass of NaOH is 60 g.
We know that molar Mass of NaOH is 39.997 g/mol. Thus;
Converting to moles, we have;
n = 60/39.997
n = 1.5 mol
Now, enthalpy when 1.5 moles of NaOH are dissolved in water will be;
ΔH = -66044 J/1.5 moles
ΔH = -44029.33 J/mol
ΔH = -44.029 KJ/mol
The burning of fossil fuels, like coal, oil, and natural gas, DO NOT contribute to the presence of greenhouse gases in the atmosphere.
True
or
False
Answer:
false statements because they are all nonrenewable resources
Which obstacle was faced by African Americans serving in the armed forces during World War II?
They were forced to serve in segregated units.
They were not subject to military conscription.
ОООО
None of them ever saw combat during the war.
They were placed under French command.
I need help plzzzzzz
Answer:
it is 25%
Explanation:
Answering so you can give the other person brainliest :D have a good day
Calculate the moles of electrons obtained from 250coulomb of electricity
Answer:
[tex]n=0.00259 mol[/tex]
Explanation:
Hello there!
In this case, since the Faraday's constant is 96500 Coulombs per mole, we can set up the following process to obtain the moles in 250 Coulombs:
[tex]n=\frac{250C}{96500C/mol}\\\\n=0.00259 mol[/tex]
Best regards!
At room temperature, oxygen is a gas and hydrogen is a gas. When they combine at room temperature, they form a _______________.
Answer: they can combine to form water or hydrogen peroxide.
Explanation:
sorry if it wrong i just looked it up lol. hope this helps tho
g The alkali metals are able to displace hydrogen readily from water. The alkaline earth metals are able to do so as well, although not nearly as vigorously. They are easily able to displace hydrogen from acid. a: Write and balance the equation for any of the alkali metals (pick your favorite!) reacting with water to form hydrogen gas and the metal's hydroxide (e.g. sodium hydroxide, potassium hydroxide). (10 points) b: Write and balance the equation for any of the alkaline earth metals (the second column on the left) reacting with hydrochloric acid to form hydrogen gas and the metal's chloride salt (e.g. magnesium chloride, calcium chloride) (10 points)
Answer:
See explanation
Explanation:
In writing a chemical reaction equation, we must ensure that it is balanced. In a balanced chemical reaction equation, the number of atoms of each element on the left hand side of the reaction equation must be equal to the number of atoms of the same atom on the right hand side of the reaction equation.
Let us now consider the reaction of NaOH with water as follows;
2Na(s) + 2H2O(l) ------> 2NaOH(aq) + H2(g)
For the reaction of Magnesium metal and HCl we have;
Mg(s) + 2HCl(aq) -------> MgCl2(aq) + H2(g)
What are the reasons to determine the melting point of a sample in a melting point apparatus? Select one or more:
A. U Assessment of the sample's purity
B. Conversion of the solid sample to liquid
C. Identification of an unknown sample
D. Removal of impurities from the sample
To prepare a sample in a capillary tube for a melting point determination, gently tap the tube into the sample with the Choose... end of the tube down. Continue tapping until the sample Choose.. end of the tube down, tap the sample down slowly or Choose... to move the sample down Then, with the Choose... faster.
To prepare a sample in a capillary tube for a melting point determination, gently tap the tube into the sample with the a) open, b) closed end of the tube down. Continue tapping until the sample a) completely fills the tube b) is a couple millimeters high, c) has a single crystal in the tube. Then, with the a) closed, b) open end of the tube down, tap the sample down slowly or a) heat the tube up, b) drop the tube into a longer tube, c) shake the tube in the air to move the sample down faster.
Solution :
The reasons for the melting point determines :
the assignment of the sample's purityidentification of the unknown samplethe conversion of solid sample to the liquid completelyIn order to prepare the sample in the capillary tube for determining its melting point, we tap the tube gently into the sample with the open end of tube down. We then continue tapping the tube till the sample is couple of millimeters high.
Then the other close end of tube down, we tap the sample down again slowly or then dropping the tube into a longer tube so as to move down the sample faster.
Analysis: Consider Joe's story. IF the test shows he does have Marfan syndrome, and if he inherited the Marfan gene from his mother, does this mean that his brother and sister also have it? You may want to draw up a Punnett Square or drawing to help you explain your answer. HINT: Is there any suggestion that he got a Marfan gene from his father?
We inherit genes from our biological parents in specific ways. One way is called autosomal dominant inheritance.
What is autosomal dominant inheritance?
Autosomal dominant inheritance means that the gene in question is located on one of the autosomes. These are numbered pairs of chromosomes, 1 through 22. (These chromosomes do not determine an offspring's gender.) Dominant means that only one gene from one parent is necessary to pass down a trait or a disorder. When a parent has a dominant trait or disorder, there is a 50 percent chance that any child he or she has will also inherit the trait or disorder:
Genetic illustration demonstrating autosomal dominant inheritance
Click Image to Enlarge
What is Marfan syndrome?
Marfan syndrome occurs in one of 5,000 live births. It is a connective tissue disorder associated with autosomal dominant inheritance. Connective tissue is abundant in the body and is important as a supporting structure. It is especially important for the musculoskeletal system. It also provides support for other body systems as well, including the eyes and the heart. The gene for Marfan syndrome is called fibrillin-1. This gene is localized to chromosome #15 on the long arm (q) at 15q21.1.
Common findings in individuals with Marfan syndrome include those related to connective tissue disorders. These include abnormal enlargement of the aortic root of the heart, dislocated lenses of the eyes, and a tall, lanky body with increased joint mobility, scoliosis, long flat feet, and long fingers. Findings may vary among individuals diagnosed with this condition, even within a family.
If an individual carries an abnormal gene for Marfan syndrome, that individual has a 50 percent risk of passing down the disorder to each future offspring. If a person does not carry the gene abnormality, then the risk for occurrence of the disorder in future offspring is the same as for the general population.
Explanation:
Anybody Understand this question please help me !
Answer:
[tex]m_{Sn}=630.57gSn[/tex]
Explanation:
Hello!
In this case, according to the chemical reaction:
[tex]SnO_2+2H_2\rightarrow Sn+2H_2O[/tex]
We can evidence the 2:1 mole ratio between hydrogen and tin, thus, we perform the following stoichiometric setup to obtain the mass of produced tin:
[tex]m_{Sn}=21.46gH_2*\frac{1molH_2}{2.02gH_2}*\frac{1molSn}{2molH_2} *\frac{118.71gSn}{1molSn} \\\\m_{Sn}=630.57gSn[/tex]
Best regards!
PLZ HELP THIS IS DUE TODAY!!!!!!
Which statement BEST describes the motion of the molecules of a solid object
A They vibrate in place within a fixed volume.
B They move around freely within a fixed volume.
C They vibrate in place and take the shape of a container.
D They move around freely and take the shape of a container.
A factory in your town uses cadmium as part of its manufacturing process. Due to recent economic conditions, cadmium is no longer available, and you must find a replacement. Suggest two elements that might be good replacements. Which of these would be your choice? Explain why.
Answer:
Zn
Explanation:
Choose a reasonable explanation to account for the differences. There may be more than one possible reason that makes sense, just select one of them.
A. It is possible not all of the water was evaporated from the sand, causing the recovered mass to be higher.
B. It is possible not all of the water was evaporated from the sand, causing the recovered mass to be lower.
C. While drying the NaCl, the liquid boiled and some splattered out of the evaporating dish, causing the recovered mass to be lower
D. While drying the NaCl, the liquid boiled and some splattered out of the evaporating dish, causing the recovered mass to be higher.
E. There was no difference in recovered and original mass, so there is no difference to account for.
Answer:
A. It is possible not all of the water was evaporated from the sand, causing the recovered mass to be higher
D. While drying the NaCl, the liquid boiled and some splattered out of the evaporating dish, causing the recovered mass to be higher.
Explanation:
Sand absorbs water and stores it. The sunlight causes the water to evaporate but sand can hold some of the water inside it. This results in increase in mass of the sand. The mass of sand before and after the water evaporation can be different.
Please please help me please please help please please help me please please help please please help me
Answer:
AU9NJ-BLVHV-TCLJS-54YTB
Helpppp!!!
Which Advantages do instrumental methods of chemical analysis have over traditional methods?
A. Accuracy, Sensitivity, identification, and automation
B. Accuracy, sensitivity, outsourcing, and automation
C. Accuracy, analysis, rapidness, and automation
D. Accuracy, sensitivity, rapidness, and expertise
E. Accuracy, sensitivity, outsourcing, and automation
Answer:
your answer would be E
Explanation:
I took that class
When a hydrocarbon fuel is burned, almost all of the carbon in the fuel burns completely to form CO2 (carbon dioxide), which is the principal gas causing the greenhouse 102 ENERGY, ENERGY TRANSFER effect and thus global climate change. On average, 0.59 kg of CO2 is produced for each kWh of electricity generated from a power plant that burns natural gas. A typical new household refrigerator uses about 700 kWh of electricity per year. Determine the amount of CO2 production that is due to the refrigerators in a city with 300,000 households.
Answer:
1.239 * 10^8 Kg
Explanation:
Since all the electricity consumed comes from natural gas;
amount of electricity consumed = 700 * 300,000 = 2.1 * 10^8 kWh
So, amount of CO2 consumed is given by;
amount of electricity consumed * amount of CO2 per kWh
Hence,
Amount of CO2 = 2.1 * 10^8 kWh * 0.59 = 1.239 * 10^8 Kg
Pls help me over here
Answer:
1 and the element is hydrogen (there is an exception for the octet rule for the element hydrogen) hope this helps
Explanation:
Convert 23.92 mm to meter
Answer:
0.02392 m
Explanation:
Kilo - Hecto - Deka - Meters/Liters/Grams - Deci - Centi - Milli
23.92 mm ---> 0.02392 m
Basically move the decimal 3 units to the left.
Hope this helps and stay safe, happy, and healthy, thank you :) !!