Nhiệt phân hoàn toàn 1,88g Cu(NO3)2.Khí bay ra cho hấp thụ vào H2O tạo thành 2 l dd A. Dd A có pH= ?
Answer: theo mình thì mình làm như sau
cu(no3)2 nhiệt phân hết
\Rightarrow nNO2= 0,02mol
nO2=0,005mol
khi hấp thụ O2 và NO2 vào nước ta có
2NO2 + 1/2 O2\Rightarrow 2HNO3
phản ứng là vừa đủ nên
nHNo3= 0,02 mol
pH HNO3=2
khi cho 0,001mol NaOH vào thì phản ứng trung hòa
H+ + OH- \Rightarrow H20
nHNO3=0,02/20=0,001
nhận thấy nH+ =nOH- nên phản ứng vừa đủ
pH của dd Y=7
theo mình giải là như vậy
Explanation:
state two application of chemistry on each of the following:-
1.forensic
2.agriculture
3.industrial
4.millitary
5.space science
EASY 30 POINTS! PLS HELP ME T-T
1. True or false? All atoms in an element contain an identical number of neutrons.
2. An atom with a _______ charge has the same number of protons and electrons.
3. An atom that has a different number of electrons and protons is called a(n) _______.
Answer:
1.false
2.neutron
3.neutron
Answer:
1. false
2. zero
3. isotopes
hope it helps
chất có ở đâu ? nước tự nhiên là chất hay hỗn hợp
Answer:
Water, H2O, is a pure substance, a compound made of hydrogen and oxygen. Although water is the most abundant substance on earth, it is rarely found naturally in its pure form. Most of the time, pure water has to be created. Pure water is called distilled water or deionized water.
underline and identify the parts of the text on this page that use examples of how the flow of the matter through a system is driven by energy and can do the work.
The parts of the text on the page that use examples of how the flow of matter through a system is energy driven and has the capacity to do work are;
1) The flow of water down rivers passing through hydro power dams to perform the following works;
River bank particle erosionElectric power generation2) The flow of electrons that corresponds to the flow of electricity (in the reverse direction) to perform the following works;
Light bulbs turn onTelevisions are powered3) The lifting of the hammer by the cam which gains gravitational potential energy that is converted to kinetic energy as the hammer drops
The hammer is repeatedly lifted and dropped by the cam to do the following work
Hammering a metal piece into shape4) The chemical potential energy stored in bonds by virtue of the relative atomic distances which produces kinetic energy from the chemical potential energy
Lear more about energy conversion here:
https://brainly.com/question/15105485
Chemical changes can change which properties of a substance?
Group of answer choices
Reactivity
Color
Malleability
All of the above
Answer:
» Reactivity and color
Explanation:
though color is very minor answer because it also relates to a physical property.
[tex].[/tex]
A pan containing 20.0 grams of water was allowed to cool from a temperature of 95.0 °C. If the amount of heat released is 1,200 joules, what is the approximate final temperature of the water?
75 °C
78 °C
81 °C
87 °C
Answer:
81 °C
Explanation:
This is a calorimetry question so a few things you will need for this. The calorimetry equation q=mcΔT & the specific heat of water (4.2J/g•°C). Other definitions are:
q = heat added/released by a sample
m = mass of sample
c=specific heat of sample
ΔT = change in temperature
from here we can rearrange the equation to state:
q/(mc) = ΔT
1200J/((20.0g)(4.2J/g•°C)) = ΔT
14°C = ΔT
If the starting temperature was 95.0°C and we know that the temperature was cooled by 14°C then the final temperature of the water would be 81.
Answer:
C. 81 c
Explanation:
took the test :)
What effect does fermented sugar have in beer brewing
Answer:
If the sugar concentration level of the must becomes too high at any given point--either at the beginning or during the fermentation--it starts to have an inhibiting effect on the yeast's ability to produce alcohol. In other words, the higher sugar concentration starts to act as a preservative effecting the fermentation in a negative way.
Explanation:
Fermentation is the process by which yeast converts the glucose in the wort to ethyl alcohol and carbon dioxide gas -- giving the beer both its alcohol content and its carbonation.
How would you change the type of atom
Answer:
Hi, There! :)
If you change the number of protons an atom has, you change the type of element it is. If you change the number of neutrons an atom has, you make an isotope of that element.
Answer:
If you change the number of protons an atom has, you change the type of element it is. If you change the number of neutrons an atom has, you make an isotope of that element. All known elements are arranged on a chart called the Periodic Table of Elements.
Explanation:
that's what I found buddy
Revision has a atoMic number of 37 and a mass number of 85. HIW many protons, neutrons and electrons does an ion of rubidium with a 1+ charge have
Answer: 37 protons, 48 neutrons, and 36 electrons.
Explanation: I assume "Revision" is Rubidium. It is atomic number 37, so it has 37 protons. It's atomic mass is 85, so it has an average of (85-37) = 48 neutrons. It has a charge of +1, so one electron of the original 37 has left.
What can we say about
protons?
A. They are in the nucleus and never
leave.
B. They move around outside the nucleus.
C. They move in and out of the nucleus.
Answer:
A. They are in the nucleus and never leave.
Explanation:
Protons as well as neutrons are located in the nucleus of the atom.
hope this helps!
what is the concentration of hydrogen ion, H+, present in a water sample if 100. ml of the sample requires 7.2 ml of 2.5 x 10 -3 M NaOH to be neutralized
Answer: 1.8x10^-4 M H+
Explanation: The number of moles of NaOH added to the 100 ml soultion will be equal to the number of moles of H+ present in that solution.
Moles NaOH in 7.2 ml of 2.5x10^-3 M NaOH
(2.5x10^-3 M NaOH) is the same as 2.5x10^-3 moles NaOH/liter
(2.5x10^-3 moles NaOH/liter)*(7.2 ml)*(1 liter/1000ml) = 1.8x10^-4 moles NaOH used to titrate 100 ml of the acid. That means there was 1.8x10^-4 moles of H^+ in 100 ml.
Concentration of H^+ = (1.8x10^-4 moles H)/0.100 l) = 1.8x10^-4 M H+
(pH of 3.74)
please answer quick...................
Answer:
3). C
Explanation:
When inter-nuclear distance [ atomic radius ] is smaller, the nuclear attraction has a greater magnitude.
[tex].[/tex]
Compare and contrast the three types of mixtures (solutions, colloids, and suspensions).
Answer:
solutions is a homogenous mixture while colloids and suspensions are heterogeneous mixtures made up of 3 or more substances
Explanation:
homogeneous- made up of one thing
heterogeneous- made up of 2 or more things
Plzzzzzz help me Write electronic configuratof sodium and chlorine in the term of subshell ?
Answer:
ans:Ne=2,8,1
ans:2,8,7
All the following process produces hematite except
A roasting of siderite
B oxidation of iron
C oxidation of magnetite
D drying of limonite
E no correct answer
Answer:
D)driying of limonite these is the answer
Calculate the no. of moles in 25gm of calcium phosphate
PLz Fast
answer/
1 grams Calcium Phosphate to mol = 0.00322 mol
no. of moles= 0.00322×25
no. of moles = 0.0805
(Physical Science)
Which group of metals includes elements with one valence electron? (1 point)
A. alkaline earth metals
B. rare earth metals
C. alkali metals
D. transition metals
Answer:
C
Explanation:
alkali metals are the Group I elements, which have 1 electron in their valence shells
Answer:
Alkali metals are the elements which have only one valence electron in their outermost or ultimate shell.
Explanation:
Alkaline Earth metals have 2 valence electron in their outermost shell and readily give up their 2 electron to achieve stability.
Rare Earth Metals have 3 valence electron in their outermost shell and they have high magnetic moments and divert range of magnetic structure.
Alkali Earth metals have 1 valence electron.
Transition metals generally have 2 valence electron .
Learn more on:
https://brainly.com/question/3062525
surely help:) I’ll brainlist!
Answer:
A. The product formed have more energy than the reactants.
This is because it is an endothermic reaction.
[tex].[/tex]
what is force ?write its effects.
Answer:A force is a push or pull upon an object resulting from the object's interaction with another object.
A force acting on an object causes the object to change its shape or size, to start moving, to stop moving, to accelerate or decelerate
If you burn a citronella candle near your picnic will it keep mosquitoes away
Answer:
Thanks!!!
Explanation:
Answer:
true
Explanation:
what are the three formula of mole?
[tex] \huge \boxed{\mathfrak{Formulas} \downarrow}[/tex]
For all[tex] \large \sf \: mole = \frac{mass}{molar \: mass} \\ [/tex]
For gases[tex]\large \sf \:mole = \frac{volume}{molar \: volume} \\ [/tex]
For solutions[tex]\large \sf \:concentration \: ( \frac{g}{ {dm}^{3} } ) \\\large \sf \: = \frac{mass(g)}{volume( {dm}^{3} )} [/tex]
You can substitute mass with mole for concentration (mol/dm³).SURELY SOMEONE HELP it’s urgent plllss I’ll brainlist u/5 star!!! answer the ones u know. :)
Answer:
3 exothermic reaction. only that much
Hi,
These are the answers.
• Question 2. C , Substance dissolves
• Question 3. D , Exothermic reaction
• Question 4. C , Endothermic reaction takes place
• Question 5. A , the products formed has more energy than reactants
Hope it helps you... pls mark brainliest if it helped you
Multiple Choice Questions 1. Which of the following statement best describes an atom? A. Protons and electrons are grouped together in a random pattern. B. Protons and electrons are grouped together in an alternating pattern C. A core of protons and neutrons surrounded by electrons. D. A core of electrons and neutrons surrounded by protons. 2. Table 5.10 shows the atomic mass of four stable isotopes of an element X. 119
Answer:
C is Correct
Explanation:
Protons and Neutrons make up the Nucleus while Electrons surround the nucleus in circular orbits with continuous rotation.
Which of these are PHYSICAL changes?
А.
cutting, tearing, freezing, thawing, folding.
mixing without chemical changes
B.
burning, rusting, forming a new substance from
two different substances, exploding, cooking
Answer:
the answer to this problem is a
Freezing water cracking limestone
a
Chemical Change
b
Physical Change
Answer:
Freezing water and cracking limestone are physical changes.
What is the mass of six of these marbles? What is the volume? What is the
density?
Answer:
All right. So let's calculate the density of a glass marble. Remember that the formula for density is mass over volume. So if I know that the masses 18.5 g. And I know that the um volume is 6.45 cubic centimeters. I can go ahead and answer this to three significant figures. So it's going to be 2.87 grams per cubic centimeter. Okay, that's our density. Now, density is an intensive process. Okay. We're an intensive property. I really should say. It doesn't depend on how much you have. Mhm. If I have one marble, its density is going to be 2.87 g per cubic centimeter. If I have two marbles, the density will be the same because I'll double the mass and I'll also double the volume. So when I divide them I'll get the same number. Okay, that's what makes it an intensive property. No matter how many marbles I have, they'll have the same density. Mass though is not an intensive property. So if I have six marbles and I want to know what the massive six marbles is. Well, I know the mass of each marble is 18.5 g. So the mass of six marbles Is going to be 100 11 g. Because mass is an extensive property. It depends on how much you have. If I change the number of marbles, I'm going to change the mass. That's an extensive property. All right. So we've calculated the density. We've calculated the mass and then what happens to the density of one marble compared to six marbles as we mentioned before. Since densities and intensive property, the densities will be the same, no matter how may.
Explanation:
Which element would most likely lose electrons to form positive ions when bonding with other elements?
rubidium (Rb)
gallium (Ga)
argon (Ar)
iodine (I)
The correct answer to the question is Rubidium (Rb)
Rubidium (Rb) is a group 1 element and as such, it can form bond by losing it's valence electron (i.e 1 electron) easily.
Gallium (Ga) is a group 13 element. It can only form bond by losing it's 3 valence electrons.
Argon is a group 18 element. This group has completely filled outermost shell and are very stable. They do not involve in bond formation.
Iodine (I) is a group 17 element. It is more difficult for this group to lose its 7 valence electrons hence, they form bond by accepting 1 electron.
With the above information, we can conclude that Rubidium will most likely lose electron to form bond.
Learn more: https://brainly.com/question/13178080
Answer:
(Question 1)Which element would most likely lose electrons to form positive ions when bonding with other elements?
(Answer) rubidium (Rb)
(Question 2) Which statement about sodium chloride is correct?
(Answer) The sodium atom transfers electrons to the chlorine atoms to form ionic bonds.
(Question 3) Based on their locations in the periodic table, which two elements are most likely to form covalent bonds with each other?
(Answer) nitrogen (N) and oxygen (O)
(Question 4) Which phrase best describes electronegativity?
(Answer) the relative strength with which an element attracts electrons in a chemical bond
(Question 5) Based on the information in the table, which pair of elements would likely form the least polar bonds with each other?
(Answer) bromine and nitrogen
Explanation:
just finished the quick check enjoy UwU
What is the control in the experiment?
Answer:
C. the amount of drug x given to mice
Sorry for the spamming, but this question is URGENT here,
Which of the following is
property of metals?
A. brittle
B. good conductivity."
C. poor conductivity
(Btw here’s a picture :O)
Option B, Metals have good conductivity.
Hope it helps you.. pls mark brainliest if it helps you
