Answer:
if na is Avogadros number then number of vaclence electron in 4.2 g of nitride ions (N3-is.2.4Na. so the answer is 2.4 na
Explanation:
Mass N3- ion = 14 g/mol. So,
4.2 g X (1 mol/14 g) = 0.3 mol N3-
Number of N3- ions = 0.3 mol X 6.02 X 10^23 ions/mol = 1.8 X 10^23 ions
Each N3- ion has 8 valence electrons, so total number of valence electrons = 1.8 X 10^23 X 8 = 1.4 X 10^24 valence electrons.
hope it helps
A student added 3 gms one substance in a beaker and then added 4 gms of another substance. A chemical reaction took place in the uncovered beaker, after the reaction the beaker weighed 5 gms which of the following is the best explanation?
A Some of the mass of the reactants was lost as heat and evaporated into the air.
B. The reaction produce a gas as a product.
C. Some of the reactantants were destroyed as when the chemicals were added.
Answer:
B. The reaction produce a gas as a product.
Explanation:
According to the law of conservation of mass, the total mass of reactants must be equal to the total mass of products because mass is neither created nor destroyed in a chemical reaction.
The total mass of the reactants is 7 grams. The total mass of the products and the beaker is 5 grams. This means that the mass of products is less than the mass of reactants.
The only plausible explanation for this is that the reaction produced a gaseous product which escaped because the system is an open system thereby leading to a lesser measured mass of products since mass can not be created nor destroyed.
What is the iupac name of CH3-CH2-CH2-OH?
Answer:
the iupac name of CH3-CH2-CH2-OH Propanol.
On the calendar provided below, the full moon is shown happening on the eleventh of the month? What moon would you see around the 25th of the month, shown with the question mark? Question 8 options: A. First Quarter B. New Moon C. Waxing Crescent D. Waning Gibbous
Answer:
The correct answer is - B. New Moon.
Explanation:
The change of moon disc from all black to all light to all dark again is called the lunar cycle. It takes almost 30 days (29.53059 to be precise). The time from all black to all light or all light to all black is almost 15 days. All black moon is termed as the new moon and all light is termed as the full moon.
As given that the full moon is shown happening on the eleventh of the month then what moon would be around 25 which is 14 days later that should be in waxing gibbous phase and almost new moon.
Thus, the correct answer is - B. new moon.
Pls help need by tomorrow.
What were the manipulated, responding, and one controlled variable from Spallanzani's
experiment?
Answer:
Answer here!
Explanation:
One controlled variable can be that they used the same setup, that is the constant between the two experiments. The manipulation was that Spallanzani used a flask without any air and a flask with air. The responding was or the dependent variable was to notice what had changed so in the experiment Spallanzani noticed that the flask with no air led to no microorganisms meaning that the theory of spontaneous generation is false.
The manipulated variable was the presence or absence of air in the flask. The responding variable was the growth of microorganisms in the broth. The controlled variable was the composition of the broth.
In Spallanzani's experiment, the manipulated variable refers to the factor that the scientist deliberately changes or manipulates. In this case, it was the presence or absence of air in the flasks. One flask had air sealed inside with the broth, while the other flask had no air present.
The responding variable is the factor that is observed or measured in response to the manipulated variable. In this experiment, the growth of microorganisms in the broth was the responding variable. Spallanzani checked for the presence or absence of microorganism growth in each flask.
The controlled variable is the factor that is kept constant or controlled throughout the experiment to ensure that it does not influence the results. In this case, the controlled variable was the composition of the broth used in both flasks. The broth composition was consistent, ensuring that any differences observed in microorganism growth could be attributed to the presence or absence of air.
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The saturation point for a solution is 50.0 grams of solute per 500 grams of solvent. How many grams of solute can be dissolved in 800. grams of solvent?
Plz help me
Answer:
I think it can dissolve 80.0 grams
CH4 + 2O2 --> CO2 + 2H2O
If you have 1 mole of CH4 and 6 moles of CO2 how many moles of CO2 and H2O will be produced?
Answer:
1 mole of CO2 and 2 mole H2O will be produced in the reaction.
Explanation:
N:B: I guess it will be 6 moles of O2 not CO2.
Balanced Equation: CH4 + 2O2 --> CO2 + 2H2O
Given,
1 mole CH4
6 moles of O2
According to Stoichiometry,
In the reaction,
2 mole O2 reacts with 1 mole CH4
1 mole O2 reacts with 1/2 mole CH4
∴6 mole O2 reacts with (1/2)*6 mole CH4
= 3 moles of CH4
But, there is only 1 mole CH4 provided. So CH4 is the limiting reagent.
Now,
According to Stoichiometry,
In the reaction,
1 mole CH4 produces 2 moles of H2O
Again,
According to Stoichiometry,
In the reaction,
1 mole CH4 produces 1 mole CO2
So, 1 mole of CO2 and 2 mole H2O will be produced in the reaction.
N:B:[Doing calculation with limiting reagent in problems like these gives you the most accurate answer].
Given the formula of a compound:
(1) aldehyde
(2) alkene
(3) alkyne
(4) alcohol
Answer:
Number 3 alkyne is the answer
Explanation:
Answer: The answer is Alkyne.
What is the equation for determining gas pressure?
PLEASE HELP
If I put more air in a car tire, which relationship does it show?
a. pressure and volume
b. temperature and volume
c. amount of gas and pressure
Selected: d. temperature and pressure
Answer:
amount of gas and pressure
What is a single-displacement reaction?
a type of reaction that occurs when two simple substances interact to form a single new, more complex compound
a type of reaction that occurs when a single substance breaks down into two or more less complex substances
a chemical reaction that occurs when a substance combines with molecular oxygen, releasing light and heat
a chemical reaction that occurs when one element within a compound is exchanged with another element
Answer:
it's the last one.
Explanation:
a compound reaction that occurs when one element within a compound is exchanged with another element.
GUYS, PLEASE HELP ME I'M ON THE LAST QUESTION AND I GET IT WRONG I HAVE TO START OVER. no links
Answer:
its actually experimental this time
Explanation:
sorry bout the last one i just wanna help:(
How many atoms are in 0.500mol of calcium?
Answer:
3.01×10²³ atoms of calcium
Explanation:
number of moles = number of atoms/Avogadro's constant
n = N/NA
N = n×NA = 0.500 mol×6.02×10²³ mol^-1
N = 3.01×10²³ atoms of calcium
Which of the following describes an impact of the specific heat of water on the planet and the life forms that exist on it?
a) places near the sea show high high temp variation
b) inland cities have moderate temperatures throughout the year
c) marine life experiences sudden spikes and drops in temperature
d) sweat requires a lot of thermal energy to be absorbed to evaporate
Answer:
The answer is D, "sweat requires a lot of thermal energy to be absorbed to evaporate."
Explanation:
Like the other person, I just took the test.
An impact of the specific heat of water on the planet and the life forms in it is: D. sweat requires a lot of thermal energy to be absorbed to evaporate.
What is thermal energy?Thermal energy is also referred to as heat and it can be defined as a form of energy that is transferred from one physical object to another, especially due to a difference in temperature.
Generally, a lot of thermal energy is required to be absorbed for sweat to evaporate and this is mainly due to the impact of specific heat of water on the planet and all the life forms that are existing on it.
Read more on thermal energy here: brainly.com/question/12072129
Given the information in the velocity vs. time graph,
what is the displacement of the object after 1 second?
After 3 seconds?
After 5 seconds?
aniapsmxuansyxineydo
At STP 101.3 kPa 0 C one mole of Ar gas was collected and was found to occupy a volume of 22.4L What is the value of the gas constant in rounded to the nearest hundredth?
Answer:
8.31 KPa.L/Kmol
Explanation:
From the question given above, the following data were obtained:
Pressure = 101.3 KPa
Temperature (T) = 0 °C = 273 K
Number of mole (n) = 1 mole
Volume = 22.4 L
Gas constant (R) =?
The gas constant can be obtained as follow:
PV = nRT
101.3 × 22.4 = 1 × R × 273
2269.12 = R × 273
Divide both side by 273
R = 2269.12 / 273
R = 8.31 KPa.L/Kmol
Therefore, the value of the gas constant is 8.31 KPa.L/Kmol
How many calories are absorbed in a process that absorbs 0.128 joules?
A. 0.031 cal
B. 0.536 cal
C. 536 cal
D. 0.310 cal
Please answer questions as soon as possible. Will be picking the brainiest answer.
Answer:
1. One is more compact than the next hence more density
2. A: 0.67g/cm3 hence will sink
B:0.56g/cm3 hence will sink
C:0.91g/cm3 hence will sink
Explanation:
Use the formula mass/volume to find its density with S.I unit is g/cm3
And to determine weather or not it sink use the relative density formula
Density of substance / Density of water
when you hold a metal coat hanger in a camp fire to roast a marshmallow, the coat hanger might get too hot to hold. what type of heat transfer is occurring between the metal coat hanger and your hand? explain what is happening at the molecular level that causes your hand to feel hot.
Answer:
Heat transfer by conduction
How many calories are absorbed in a process that absorbs 0.128 joules?
Answer:
There are 0.0305 calories in 0.128 joules
Explanation:
Given that,
Heat absorbed, Q = 0.128 J
We need to find the heat energy absorbed in calories.
We know that the relation between joules and calories is as follows :
1 calorie = 4.184 J
1 J = (1/4.184) J
So,
[tex]0.128\ J=\dfrac{0.128 }{4.184}\\\\=0.0305\ cal[/tex]
So, there are 0.0305 calories in 0.128 joules
How do scientists verify the results of an experiment?
by analyzing results
by communicating with other scientists
by collecting data
by repeating the experiment
Answer:
by repeating the experiment
Explanation:
sometimes repeating the experiment with multiple trials can help make the experiment worth it
Please help!!! If u reply with a link i will report
M = mRT/PV
Use the equation above to find the molar mass of a 98.2 g sample of gas that fills a 50.0 liter container at STP
a. 4.00 g/mol
b. 44.0 g/mol
c. 1.48 g/mol
d. 32.0 g/mol
6.
What are the mass numbers of; hydrogen, helium
and boron? I
승
please just help me.
Answer:
∆H= 3.92 kJ
∆S= 2.54 J
Explanation:
Hope It helps
Which of these describes a similarity between nuclear energy and fossil fuel?
A. Both release products with short half-lives.
B. Both fuels have the same energy density.
C. As both fuels undergo reactions, heat is released, which is used to
do work.
D. The cost of storing both fuels is expensive.
SUBMIT
The similarity between nuclear energy and fossil fuel is "as both fuels undergo reactions, heat is released, which is used to do work."
What is nuclear energy?Nuclear energy is the type of power produced when a nuclear reaction releases energy. Nuclear energy was exemplified mostly by the electricity generated by just a nuclear reactor, which is Japan's principal source of energy.
What is fossil fuel?Fossil fuel is just a hydrocarbon-containing component that occurs naturally in the earth's crust and is collected and being used as a fuel. The most popular fossil fuels are coal, crude oil, and natural gas.
Therefore, similarity between nuclear energy and fossil fuel is both fuels undergo reactions, heat is released, which is used to do work.
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Can someone help me please
Answer:
I believe the answer is C.
Answer:
C
Explanation:
green house gases effects increases global warming
what is the answer of this Al2(SO3)3 + NaOH g Na2SO3 + Al(OH)3
Answer:
Al2(SO3)3 + 6NaOH → 3Na2SO3 + 2Al(OH)3
Which phrase describes a volcano that is not expected to erupt again?
1 quiet volcano
2 extinct volcano
3 dormant volcano
4 explosive volcano
Answer:
Extinct
Explanation:
Extinct volcanos are not expected to erupt, and have not erupted in a very long time.
Oxidation, or the loss of electrons, will result in an element becoming _____ positive. This element will show a(n) _____ in oxidation number. Reduction, the gain of electrons, will cause an element to become _____ positive and the element will show a(n) _____ in oxidation number.
Answer:
1)more
2) increase
3)less
4)decrease
Explanation:
Oxidation can be regarded as process involving loss of electrons when a reaction is taking place by an atom or molecule, atom as well as ion. Oxidation do take place as when there is increase in oxidation state of a molecule as well as atom or ion. Reduction which is opposite process takes place as a result of gain in electrons, or when there is decrease in oxidation state of an atom as well as molecule, or ion. Oxidation number gives the the number which is been allocated to elements during a reaction of chemical combination. It gives the count of sharable electrons for an atoms or electron it can gain or loose as chemical bonding is taken place.
It should be noted Oxidation, or the loss of electrons, will result in an element becoming more positive. This element will show an increase in oxidation number. Reduction, the gain of electrons, will cause an element to become less positive and the element will show a decrease in oxidation number.
what is a major disadvantage of crude oil as an energy resource ?
Answer:
Burning oil can pollute the air. Much of our oil has to be imported and it is becoming more and more expensive as reserves reduce and imports increase. Producing electricity from crude oil is expensive compared to other fossil fuels such as coal or gas.
Explanation:
If the [H+] in a solution is 1.0 x 10-7M, what is the [OH-] of this solution?
A. Higher than [H+]
B.lower than [H+]
C.same as [H+]
Answer:
C.same as [H+]
Explanation:
Autoionization of water is expressed as H+ * OH- = Kc
The value of Kc is 1*10^-14. Now simply plug thus in and the value of given H+ to solve
(1*10^-7) * OH- = 1*10^-14
OH- = 1*10^-7
Thus, in this scenario, the H+ and OH- ions have same concentration and solution is said to be neutral.