Answer: [tex]1.07\times 10^{23}[/tex] molecules
Explanation:
According to the ideal gas equation:
PV=nRT
P = Pressure of the gas = 1 atm ( at STP)
V= Volume of the gas = 4.00 L
T= Temperature of the gas in kelvin = 273 K ( at STP)
R= Gas constant = 0.0821Latm/kmol
n= moles of gas= ?
Putting in the values we get:
[tex]1atm\times 4.00L=n\times 0.0821Latm/Kmol\times 273K[/tex]
[tex]n=0.178mol[/tex]
Now 1 mole of any substance contains [tex]6.023\times 10^{23}[/tex] molecules at STP
Thus 0.178 mole of any substance contains = [tex]\frac{6.023\times 10^{23}}{1}\times 0.178=1.07\times 10^{23}[/tex] molecules at STP
Thus there are [tex]1.07\times 10^{23}[/tex] gaseous molecules in the flask.
74.7 g of Calcium Chlorate = __mol
Answer:
747 mol.
Explanation:
What effect does temperature have on reaction rate?
Answer:
Increasing the temperature increases reaction rates because of the disproportionately large increase in the number of high energy collisions.
Explanation:
Hope this helps :)
Calculate the number of grams of HNO3 which must be added to 31.5 g of H20 to prepare a 0.950 m solution.
Answer:
1.89g of HNO3
Explanation:
Data obtained from the question include:
Mass of water = 31.5 g
Molality of HNO3 = 0.950 m
Mass of HNO3 =.?
Next, we shall determine the number of mole of HNO3 in the solution.
Mass of water = 31.5 g = 31.5/1000 = 0.0315 Kg
Molality of HNO3 = 0.950 m
Number of mole of HNO3 =..?
Molality is simply defined as the mole of solute per unit kilogram of solvent (water) i.e
Molality = mole /kg of water
With the above formula, the mole of HNO3 can be obtained as follow:
Molality = mole /kg of water
0.950 = mole of HNO3 /0.0315
Cross multiply
Mole of HNO3 = 0.950 x 0.0315
Mole of HNO3 = 0.03 mole
Finally, we shall convert 0.03 mole of HNO3 to grams. This is illustrated below:
Molar mass of HNO3 = 1 + 14 + (16x3) = 63g/mol
Mole of HNO3 = 0.03 mole
Mass of HNO3 =..?
Mole = mass /molar mass
0.03 = mass of HNO3 /63
Cross multiply
Mass of HNO3 = 0.03 x 63
Mass of HNO3 = 1.89g
Therefore, 1.89g of HNO3 is needed to prepare the solution.
Which of the following is a correct observation when water is added to quick lime?
A .Vigorous bubbling and a hissing sound both.
B .Slow bubbling with no sound.
C .Vigorous bubbling with evolution of heat and a hissing sound.
D. No change.
Answer:
c
Explanation:
thw observation of water that is added
Which of the following describes what happens in a chemical reaction?
O A. Molecules change from one phase to another.
B. Molecules dissolved in solution are separated again.
O c. Chemical bonds are broken, and new ones are formed.
O D. Molecules mix without rearranging atoms.
Answer:
c. Chemical bonds are broken, and new ones are formed.
Explanation:
Hope this helps. :)
In a chemical reaction, chemical bonds are broken, and new ones are formed.
What is a chemical reaction?Chemical reactions are defined as reactions which occur when a substance combines with another substance to form a new substance.Alternatively, when a substance breaks down or decomposes to give new substances it is also considered to be a chemical reaction.
There are several characteristics of chemical reactions like change in color, change in state , change in odor and change in composition . During chemical reaction there is also formation of precipitate an insoluble mass of substance or even evolution of gases.
There are three types of chemical reactions:
1) inorganic reactions
2)organic reactions
3) biochemical reactions
During chemical reactions atoms are rearranged and changes are accompanied by an energy change as new substances are formed.
Learn more about chemical reactions,here:
https://brainly.com/question/29762834
#SPJ2
A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion. B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion. C. If Assertion is true statement but Reason is false. D. If Assertion is false and Reason is true i Assertion: .Burning of magnesium ribbon produce whitish powder called magnesium oxide. Reason : Magnesium is generally cleaned by rubbing it on sand paper
Answer:
C. If Assertion is true statement but Reason is false.
Explanation:
The burning of magnesium in air produces magnesium oxide as shown by the equation;
2Mg(s) + O2(g) -----> 2MgO(s)
The magnesium oxide solid is recovered as a white ash. This is a typical example of an oxidation reaction which is also a combustion reaction.
The reason has nothing at all to do with the assertion hence the answer given.
Magnesium oxide is basic just like the oxides of other metals and dissolves in water to yield an alkali.
Answer:
Answer:
C. If Assertion is true statement but Reason is false.
Explanation:
The burning of magnesium in air produces magnesium oxide as shown by the equation;
2Mg(s) + O2(g) -----> 2MgO(s)
The magnesium oxide solid is recovered as a white ash. This is a typical example of an oxidation reaction which is also a combustion reaction.
The reason has nothing at all to do with the assertion hence the answer given.
Magnesium oxide is basic just like the oxides of other metals and dissolves in water to yield an alkali.
Explanation:
What are the periodic trends of ionic radii? Check all that apply. Ionic radii tend to increase down a group. Ionic radii tend to decrease across a period. Anionic radii tend to increase across a period. Cationic radii tend to decrease across a period. Ionic radii increase when switching from cations to anions in a period.
Answer:
What are the periodic trends of ionic radii? Check all that apply.
*Ionic radii tend to increase down a group.
Ionic radii tend to decrease across a period.
Anionic radii tend to increase across a period.
*Cationic radii tend to decrease across a period.
*Ionic radii increase when switching from cations to anions in a period.
Answer:
- Ionic Radii Tend To Increase Down A Group.
- Cationic Radii Tend To Decrease Across A Period.
- Ionic Radii Increase When Switching From Cations To Anions In A Period.
Explanation:
i got it correct on edge
What is an exothermic reaction? Combustion of fuel is an exothermic process. Explain why by providing an example of a fuel. Give 3 examples of readily observable reactions that are considered exothermic. In each example, describe the reactants and the products.
Answer:
An exothermic reaction is a chemical reaction in which energy is given out to the surroundings in the form of heat or light or even sound.
Other explanations are given below.
Explanation:
An exothermic reaction is a chemical reaction in which energy is given out to the surroundings in the form of heat or light or even sound. In exothermic reactions, the energy content of the products are lower than that of the reactants and this excess energy is therefore released as the reaction proceeds towards formation of products.
Combustion of fuel is an exothermic reaction because the process involves the release of energy in the form of heat and light to the surroundings as the reactants (usually a fuel and oxygen) which are at a higher energy state combine to give the products which are at a lower energy state (usually CO₂ and water).
An example of a fuel is the gas propane found in cooking gas. It combines with oxygen found in air to produce the heat that is used to cook our foods.
Other examples of exothermic reactions include
1.Lighting firewood: In this process, wood which is a mixture of gaseous fuels like methane and solid fuel like charcoal combine with oxygen found in air to produce carbon (iv) oxide and water vapor while releasing heating the process.
2. Lighting a match: The head of safety matches are made of potassium chlorate, mixed with sulfur, fillers and glass powder. The side of the box contains red phosphorus, binder and powdered glass. When the match is struck, the friction generates heat which causes a small amount of red phosphorus to be converted to white phosphorus, which then ignites spontaneously in air. The heat produced initiates the decomposition of potassium chlorate to give oxygen and potassium chloride. The sulfur catches fire and ignites the wood which also burns in the air to release carbon (iv) oxide an water.
3. Burning of coal: Coal is solid carbon which combines with oxygen in air when ignited to produce carbon (iv) oxide and water vapor while also releasing heat and light energy.
Based on the law of Conservation of Mass, what happens to the mass of a substance in a chemical change? A: the mass is always conserved B: The mass is either created or destroyed C: the reactant always has more mass D: the product always has more mass
Answer:
A.
Explanation:
The amount of mass always stays the same, matter cannot be created nor destroyed, it can only change forms. Thus, the answer is A.
In a chemical reaction the total mass of all the substances taking part in the reaction remains the same. Also, the number of atoms in a reaction remains the same. Mass cannot be created or destroyed in a chemical reaction.
I hope this helps..
CAn someone help me and give me an example of a process that you notice or use each day that obyes the law of conservation of mass and explain how this process work??? please answer I need a new example not burning fire or candle or paper different helppppppppppppppppppppppppppppppppppppppppp
Answer:
photosynthesis maybe
Explanation:
bare with me i may be wrong or i may be right it's been a while since i've been in a chem classroom. so basically during photosynthesis a plant is taking the energy from the sun, H2O, and CO2, this ends up being like 6CO2 + 6H20 + (energy), and it converts this energy to glucose (→ C6H12O6 + 6O2 ) so the energy is never used up in this process it is merely changed. i don't really know but i hope it at least helps some
Which tool was used to collect the solid product of the chemical reaction? the balance the funnel with the filter paper the Erlenmeyer flask the beaker the watch glass With this tool, the could be separated from the .
Answer:
B. The Funnel withe the filter paper.
Explanation:
The next answers is copper and aqueous solution.
The statement, that describes tool was used to collect the solid product of the chemical reaction is "the funnel with the filter paper."
What is a chemical reaction ?
A chemical reaction is a process that converts one or more compounds, known as reactants, into one or more distinct substances, known as products.
Filtration is a basic process for removing solid particles suspended in a liquid solution. Filtration is a method of separating solids from liquids or gases by employing a filter material that enables the fluid but not the solid to pass through. A funnel with filter paper can be used to gather solid product during the filtration process.
Hence the correct answer is the funnel with the filter paper.
Learn more about chemical reaction here
https://brainly.com/question/17053196
#SPJ2
select all the correct answers. Which conditions are required for nuclear fusion to begin? The gas cloud must be very dense. Gravitational attraction must stop. Atoms must be stripped of their electrons. Helium atoms must break down into hydrogen. Temperatures must exceed 14 million Kelvin.
Answer:
The gas cloud must be very dense.Temperatures must exceed 14 million Kelvin
Nuclear fusion is the process in which atomic nuclei come together to form heavier nuclei, releasing large amounts of energy in the process. The correct statements are The gas cloud must be very dense, Atoms must be stripped of their electrons, and Temperatures must exceed 14 million Kelvin.
For fusion to occur, certain conditions must be met. The gas cloud or plasma must be dense enough to allow for a sufficient number of collisions between atomic nuclei. Gravitational attraction, on the other hand, is necessary to bring the atomic nuclei close enough together for the strong nuclear force to overcome the electrostatic repulsion between positively charged nuclei.
Atoms must be stripped of their electrons because, in a plasma state, the atoms are ionized, meaning they have lost or gained electrons and exist as charged particles.
Hence, the correct statements are The gas cloud must be very dense, Atoms must be stripped of their electrons, and Temperatures must exceed 14 million Kelvin.
Learn more about nuclear fusion here:
https://brainly.com/question/14019172
#SPJ 2
Gold and Platinum are found in free state in nature-Give reason.
11. Which of the following is true about nitrogen-14 and nitrogen-16?
A.They are isotopes of the same atom.
B.They are the same except that carbon-14 has 2 extra electrons.
C.They are completely different atoms.
D.They are the exact same atom.
Answer:
The answer is option A.
They are isotopes of the same atom.
Hope this helps you
Which missing item would complete this beta decay reaction?
Answer:
The answer is option A.Hope this helps you
explain with the help of Balanced equation how precipitation reaction are used for identifying the positive radicals in three different salts each having a different positive ion
Answer:
The balanced equation related to them is given below.
Explanations:
Precipitation involves the reaction that occurs in acidic suspension as charged particles (two) come together to generate other unfixable or unsolvable salts which are known as that of the precipitate.A specific method of describing a reaction from precipitation becomes recognized as that of the binary ionic formula. Throughout this scenario, certain spectator ions being generally left out from under the calculation.The reaction will be:
⇒ [tex]Ag+(aq) + Cl^-(aq) \rightarrow AgCl (s)[/tex]
Match the following.
1. A substance that produces hydrogen ions in solution; alternatively, a proton donor
2. A substance that produces hydroxide ions in solution; alternatively, a proton acceptor
a. acid
b. base
Answer:
1. Acid produces hydrogen ions in a solution.
2. Base produces hydroxide ions in a solution.
Answer:
1. A substance that produces hydrogen ions in solution; alternatively, a proton donor
Acid
2. A substance that produces hydroxide ions in solution; alternatively, a proton acceptor
Base
Philosophy ultimately seeks to discover ultimate truth
True or false
Answer:
True
Explanation:
Phislosophy does not accept something even though it is a khown fact unless it can proves it's true .
Descartes sais that in philosophy we must doubt the facts we khow , we must start from the beginning to reach the truth
write down the new substance formed when ammonia react with hydrochloric acid
Answer: ammonium chloride
Explanation: The reaction equation among ammonia (NH3) and hydrochloric acid (HCl) is written as follows: NH3+HCl=NH4Cl. Ammonia is a susceptible base that reacts with hydrochloric acid, forming a compound referred to as ammonium chloride.
Simplify :: 3/8 + 7/2 + (-3/5) + 9/8 + (-3/2) + 6/5
Answer:
4.1/ [tex]\frac{41}{10}[/tex]
Explanation
Do the calculation carefully because this calculation has negative term.
I hope you will understand.
3/8 + 7/2 + (-3/5) + 9/8 + (-3/2) + 6/5
31/5+(-3/5)+(-3/2)
41/10
4.1
Study the following reaction: NH4+(g) + NO2⁻(g) ⟶ N2(g) + 2H2O(l) How does the rate of this reaction change when the temperature is increased? A) The rate decreases because a higher temperature means that particles move at higher speeds and there are more collisions in the system. B) The rate decreases because a higher temperature means that particles move at lower speeds and there are fewer collisions in the system. C) The rate increases because a higher temperature means that particles move at lower speeds and there are fewer collisions in the system. D) The rate increases because a higher temperature means that particles move at higher speeds and there are more collisions in the system.
Answer:
D). The rate increases because a higher temperature means that particles move at higher speeds and there are more collisions in the system.
Explanation:
The rate of the given chemical reaction would rapidly increase with an increase in temperature as the higher temperature will increase the kinetic energy possessed by the reactant molecules. This will lead to the movement of particles at a higher speed and more effective collisions will take place(as the greater proportion of molecules will have the energy required for collision). Thus, the last statement correctly justifies this description and hence, option D is the correct answer.
One intresting note is that bleach has a lower measured pH than given based on its color. Why is that? (Hint: what is bleach used for)
It is used for cleaning and other use. Higher pH means stronger base.
Anyone know how to answer this?
Answer:
i metal
ii nonmetal
iii metal
iv nonmetal
Explanation:
If you look up what the element of a heater is, you get a picture of some sort of rod. It's the heating element of the heater, and must be some type of metal to conduct electricity and warm up. Fishing rods are made of either fiberglass, graphite, or carbon fibre. These are nonmetals. In order for a lightning rod to conduct electricity and bring the lightning down to the ground, it has to be metal. You wouldn't want a metal oven mitt, as that would burn your hand.
While camping you light a small campfire, initiating the combustion of wood to produce heat and
light. What can you determine about this reaction?
O A. It is exothermic.
B. The bond making energy is more than 600 kJ.
OC. It is endothermic.
D. The bond breaking energy is more than 600 kJ.
Answer:
A. It is exothermic
Explanation:
Combustion is a chemical reaction in which a substance combines with oxygen present in air to produce carbon (iv) oxide and water as well release heat and light energy.Combustion is an exothermic process.
An exothermic reaction releases energy in the form of heat to the surroundings. The energy required to break bonds in the reactants is less than the energy required to form new bonds in the products in an exothermic reaction.
From the given options;
A. It is exothermic is determinable since the reaction is a combustion reaction
B. The bond making energy is more than 600 kJ is not certain because the mass of the wood being burnt is not given. Also, wood is not composed of a specific element that would be taking part in the reaction, rather it is composed of various substances.
C. It is endothermic. is wrong because combustion of wood is exothermic.
D. The bond breaking energy is more than 600 kJ is not certain because the mass of the wood being burnt is not given. Also, wood is not composed of a specific element that would be taking part in the reaction, rather is composed of many substances.
Calcium (Ca) has an atomic number of 20. It can form an ion by losing 2
electrons. What would its charge be?
A. 18
B. 22
C. 2+
D. 2-
Answer:
2+
Explanation:
Apex lolz
How to get a catalyst back at the end of a chemical reaction?
Answer:
You should get the catalyst back already.
Explanation:
A catalyst shouldn't be used up during a chemical reaction. It is used to speed up a reaction, but it shouldn't disappear/be used up by a chemical reaction.
Which of the following is NOT an indicator of a chemical
reaction?
O A. Breaking into small pieces
OB. Producing a solid
OC. Changing color
OD. Producing light
Answer:OD. Producing light
Explanation:
what is the volume occupied by 4 grams of oxygen at room temperature
Answer:
volume of O2 = 3000cm³
Explanation:
no. of moles= mass of oxygen (g)/molar mass of oxygen(g/mol)
= 4/32
=0.125
volume of oxygen= no. of moles × 24000 cm³ (or 24dm³)
= 0.125 × 24000 cm³
=3000cm³ (or 3dm³)
Which property of the isotopes must be different?
A) The atomic number
B) The electric charge
C) The element name
D) The mass number
Magnesium reacts with fluorine to form magnesium fluoride. Which diagram shows the correct arrangement of electrons in the product?
Answer:
Diagram B shows the correct arrangement of electrons in the product.
Magnesium reacts with fluorine to form magnesium fluoride two electrons of magnesium are transferred to the 2 atoms of fluorine and fluorine is the most electronegative element of the periodic table. Option C is correct.
What is electronegativity?Electronegativity is the tendency or power of an atom to attract the electrons from the metals they are mostly nonmetals and want to complete their octave too.
The most electronegative elements of the periodic table are oxygen, nitrogen, and fluorine, as they are always willing to complete the octave, and fluorine will take electrons from magnesium.
Therefore, Option C is correct if the 2 atoms of fluorine and fluorine are the most electronegative element of the periodic table. Magnesium reacts with fluorine to form magnesium fluoride two electrons of magnesium are transferred.
Learn more about electronegativity, here:
https://brainly.com/question/17762711
#SPJ6