Answer:
See explanation
Explanation:
According to the question Copper is obtained from the original alloy and the copper wire used to displace the silver.
So,
Mass of the copper from the original alloy: (10.00 % * 1.250 g) = 0.125 g
We now need to obtain the mass of the copper from the wire, then we consider how much silver is precipitated:
Mass of silver in the alloy; 90.00 % * 1.250 g = 1.125 g
So,
Amount of silver precipitated =
1.125 / 107.9 = 0.01043 mole
From the reaction equation, it takes two moles of silver to displace one mole of copper.
Hence, the amount of copper from the wire is: 0.01043 / 2 = 0.005213 mol
And a mass of 0.005213(63.55) = 0.3313 g
Total mass of copper= 0.125 + 0.3313 = 0.456 g
By the reaction between
H3PO4 and Ca(OH)2,
Can be formede:
a. Ca(HPo4)2,
b. СaHP4
c. Ca(H2PO4)2
d. Ca2HP02
e.Сa3(PO4)2
the correct answers : b, c, e
the question is:
I am preparing for an admittion test in chemistry, I face this kind of questions which I dont how to understand or if I should only memorize.
I appreciate all your help.
thank you alot.
Answer:
ANSWER is E
Explanation:
2H₃PO₄ + 3Ca(OH)₂→ 6H₂O + Ca₃(PO₄)₂
Answer:
First step is to find what the products would be. Since this seems to be a double displacement, you get: H3PO4(aq)+Ca(OH)2(aq)→ H2O(L)+Ca3(PO4)2(s)
You know the products because H has a charge of +1, so PO4 must have a charge of -3, and since OH has a charge of -1, Ca must be +2. Then make each compound have a net charge of 0. H20 is a liquid since aq solutions have liquid water. Ca3(PO4)2 is a solid, use the solubility rules.
Lastly, balance the equation: 2H3PO4(aq)+3Ca(OH)2(aq)→ 6H2O(L)+Ca3(PO4)2(s)
So the salt formed is Ca3(PO4)2
Which form of energy increases in an object as you raise it higher off the ground?
A. Electrical
B. Kinetic
C. Mechanical
D. Potential
Answer:
D. Potential
Explanation:
Answer:
Potential
Explanation:
Gravitational potential is the energy the object has of it's position of the earth's surface. When the object is lifted, work is done. When work is done in raising the height of an object, energy is transferred as a gain in the gravitational potential energy of the object.
STEP 7: LEAD
Initial temperature of metal = 100
✓°C
Initial temperature of water = 22.6
✓ °C
Final temperature of both = 23.3
°C
Subtract to find the temperature
changes for the water and the metal.
AT (water) = 0.7 ✓ °C
AT (metal) = 76.7 ✓ °C
Answer:
answer is 76
Explanation:
pls mark me brainliest right
Answer:
0.7
76.7
this is for (LEAD) the last one
Compare and contrast the three states of matter liquid, solid, and gas.
Answer:
For example: water is liquid, ice is solid, and water vapor is gas
Explanation:
What are the products from the following double - replacement reaction ? BaCl 2(aq) +K 2 SO 4(aq) a . BaSO 3 and KCI b. and KClO 4 c. BaSO 3 KClO 4 d. BaSO 4 and KClO 4 e . BaSO 4 and KCI
Answer:
e. BaSO4 and KCI.
Explanation:
Hello there!
In this case, given the reactants side:
[tex]BaCl_ 2(aq) +K_ 2 SO_ 4(aq)[/tex]
It is possible to realize that after the reaction takes place barium replaces potassium and therefore barium sulfate and potassium chloride are formed:
[tex]BaCl_ 2(aq) +K_ 2 SO_ 4(aq)\rightarrow BaSO_4(s)+2KCl(aq)[/tex]
Therefore, the products turn out to be e. BaSO4 and KCI.
Best regards!
A sample of aluminum, which has a specific heat capacity of 0.897·J·g−1°C^−1 , is put into a calorimeter (see sketch at right) that contains 300.0g of water. The aluminum sample starts off at 94.5°C and the temperature of the water starts off at 21.0°C .When the temperature of the water stops changing it's 23.8°C .The pressure remains constant at 1atm .Calculate the mass of the aluminum sample.
Answer: The mass of aluminium sample is 55.4 gram
Explanation:
[tex]Q_{absorbed}=Q_{released}[/tex]
As we know that,
[tex]Q=m\times c\times \Delta T=m\times c\times (T_{final}-T_{initial})[/tex]
[tex]m_1\times c\times (T_{final}-T_1)=-[m_2\times c\times (T_{final}-T_2)][/tex]
where,
[tex]m_1[/tex] = mass of aluminium = ?
[tex]m_2[/tex] = mass of water = 300.0 g
[tex]T_{final}[/tex] = final temperature = [tex]23.8^0C[/tex]
[tex]T_1[/tex] = temperature of aluminium = [tex]94.5^oC[/tex]
[tex]T_2[/tex] = temperature of water = [tex]21.0^oC[/tex]
[tex]c_1[/tex] = specific heat of aluminium = [tex]0.897J/g^0C[/tex]
[tex]c_2[/tex] = specific heat of water = [tex]4.184J/g^0C[/tex]
Now put all the given values in equation (1), we get
[tex]-[m_1\times c_1\times (T_{final}-T_1)]=[m_2\times c_2\times (T_{final}-T_2)][/tex]
[tex]-[m_1\times 0.897\times (23.8-94.5)^0C]=[300.0g\times 4.184\times (23.8-21.0)][/tex]
[tex]m_1=55.4g[/tex]
Therefore, the mass of aluminium sample is 55.4 gram
a'Zorria Ward
An elevator traveled 15 floors (150 ft) at a speed of 4.5 m/s. What additional information is needed to determine the velocity of the elevator?
the direction the elevator traveled
how long the elevator was stationary
O how many times the elevator stopped
O the total mass of the elevator plus anything in it
Answer:
Velocity includes Direction
So you need to know if it was going up or down
Explanation:
Somebody help me asap please giving brainliest
Answer:
fire > rocks > air
Sound waves vibrate your eardrum, which moves bones in your middle
ear. The soundwaves then pass through a fluid in your inner ear, and on to
tiny hairs that send signals to the brain.
A. True
B. False
Answer: A. True
Explanation:
Which of the following is true according the the Arrhenius theory of bases?
Question 5 options:
A strong base increases the OH- ion concentration in an aqueous solution.
A strong base increases the H+ ion concentration in an aqueous solution.
A strong base decreases the OH- ion concentration in an aqueous solution.
A strong base decreases the H+ ion concentration in an aqueous solution.
Answer:
A strong base increases the OH- ion concentration in an aqueous solution.
Explanation:
According to the Arrhenius theory, acids donate H+ and bases donate OH- to a solution.
30 points for answering: Solve all 4 questions.
1. Listening to the radio is an example of _______ energy.
A. sound
B. light
C. heat
D. chemical
2. Turning on and listening your favorite TV show is an example of:
E. light energy to kinetic energy
F. electrical energy to sound energy
G. heat energy to light energy
H. sound energy to chemical energy
3. Eating a taco is an example of ______ energy.
I. light
J. chemical
K. sound
L. heat
4. A rabbit eating grass and then running away from a coyote is an example of:
M. light energy to heat energy
N. sound energy to light energy
O. chemical energy to electrical energy
P. chemical energy to mechanical energy
Answer:
1. Sound
2.heat energy to light energy
3.chemical
4.chemical energy to electrical energy
Explanation:
Answer:
1. A
2. F
3. J
4. P
Explanation:
1. A. sound
2. F. electrical energy to sound energy
3. J. chemical
4. P. chemical energy to mechanical
explain the variation of basicity in group III A members down the group
Answer:
Explained below
Explanation:
Group 3A elements are made up of the metalloid - boron (B) and other metals such as Aluminum (Al), gallium (Ga), indium (In), & thallium (Tl).
Now, as we go down the group, the size of the central atom will increase thereby causing the lone pair to become delocalized over a larger volume space. Thus, it's not readily available for donation and thus basicity increases
Field foresters are associated with which of the following types of forestry?
urban
national
international
private sector
Answer:
urban and private sector
Explanation:
Hey! I was wondering how to get the solution to this question!
A solution was prepared by dissolving 0.541 g of benzoic acid (HC6H5COO) in 100 mL of
water. The pH was measured to be 2.78. What is the Ka for benzoic acid?
Answer:
6.22 × 10⁻⁵
Explanation:
Step 1: Write the dissociation reaction
HC₆H₅COO ⇄ C₆H₅COO⁻ + H⁺
Step 2: Calculate the concentration of H⁺
The pH of the solution is 2.78.
pH = -log [H⁺]
[H⁺] = antilog -pH = antilog -2.78 = 1.66 × 10⁻³ M
Step 3: Calculate the molar concentration of the benzoic acid
We will use the following expression.
Ca = mass HC₆H₅COO/molar mass HC₆H₅COO × liters of solution
Ca = 0.541 g/(122.12 g/mol) × 0.100 L = 0.0443 M
Step 4: Calculate the acid dissociation constant (Ka) for benzoic acid
We will use the following expression.
Ka = [H⁺]²/Ca
Ka = (1.66 × 10⁻³)²/0.0443 = 6.22 × 10⁻⁵
Baking soda (NaHCO3, 84.0 g/mol) requires acids from other ingredients to generate the carbon dioxide needed to make bread rise. The following equation describes this reaction, where HB is some unspecified acid. If 20.4 g of baking soda are used in a recipe and enough acid is present for a complete reaction, how many moles of carbon dioxide are generated?
HB + NaHCO3 ⟶ H2O + CO2 + NaB
a. 0.243 mol
b. 0.204 mol
c. 0.334 mol
d. 0.232 mol
e. 0.464 mol
Is this statement true or false?
One body system maintains the constant internal environment of the whole body.
12.0 grams of sodium reacts with 5.00 grams of chlorine. What mass of sodium chloride could be produced?
Please show work if you can. I have the limiting reactant which is Cl2 (0.0705)
I think I did this part correctly but I don't know what to do after. How do you determine the amount of sodium chloride that can be produced?
Answer❣
The required speech is as follows :
_______________
"Whoever controls media, controls mind". A very hearty Good Morning to one and all present here ! Respected Principal Sir, worthy teachers and all my dear fellow mates. Today I Aurora, of class XYZ is standing before you in this frizzy winter to deliver a short speech on the topic 'How media influences public opinion'.
Dear friends, first of all I would like to ask you all a question, 'What do you think is our media for ?' Most of us will reply that they are for our entertainment, fun and even unfortunately some will reply 'for movies and Bollywood'. Now if we look back at our history during 18th century we see that even first newspapers were started for spreading information in mass. Earlier literacy rate of India was very low.
A single person used to first read the newspaper and then shared the information to the gathered people around. But that time was different. Now nearly every person has a mobile phone, TV, PC and what not. Has this increased public participation in Democracy ? Yes indeed it has done that. On one single click we get information of our surrounding at a faster pace. As a fourth pillar of Democracy it makes our mindful of different social, political and financial exercises around us.
If we take current situation, most of the election popularisation works in different states is being managed by mass media only due to its advancements. Media makes participation of people in political activities even at grass - root levels. This efficiency enhances the Federalism of India. Media has many roles in shaping public opinion in our society. Let's discuss them one by one. In economic terms, media shows the expenditure, budgets and taxes to the citizens of a nation.
It makes people aware of the different types of money related issues that they have to face. Even it checks that no people are harassed by fake news on balances. Its makes people rise over their concern directly to the government so that actions can be taken for them. In social terms, media promotes the functioning of the government. It helps people to convey their social problems to the government. Even many NGOs and Human Rights Organizations take help of medias to make people aware of their rights.
Commonly Media acts as an inference or better to say 'compass' which gives direction to the views of people. It organises the vast multitudes of opinions into a single issue which can be beneficial to all the groups of society. It works 24 × 7 and makes people get in touch with latest developments. As 'Opposition' in Politics, media acts as a hub where the opposition party by taking views of public claims the wrong decisions of Ruling Party.
Also, during elections media shows mirror about different parties to people so that we can make right decision in voting. All these were some positive aspects of media's influence on public opinions. Now let's discuss about some negative aspects also. Nowadays its a common seen trend that media enlarges a short issue just to gain popularity. This results in riots, violence, protests, etc. because the issue which could have been solved by a single subtle discussion, now has been made a larger issue.
Let me present an example. I have a friend, Cupicake. She remains quite much familiar with medias. Some days ago, she received a post which asked her to share the image attached with it to her other friends. That image was of a case where Police was beating a few groups of people. She has shared that. This led a immediate violence in that region and finally it was known that Police was beating a few robbers. Now who to put blame of that riot ? Of course we are the one who done it.
At last I would like to conclude my speech by just saying that, it is the duty of media to transfer right and reliable information to people and its duty of people to share and trust upon right information from a good source. In this way the world and the nation would be leaded to right path.
Thank you one and all.
_______________
★ More to know :-
Format of Speech :
*Note - Here I used name as Aurora. You can use any according to your choice and class also according to the situation.
✌✌✌✌✌✌✌✌✌✌✌✌
hope that u r helpful
please follow thank and brinlylist please
Thank You...♡♡
25. What is a subdivision of a family? *
O kingdom
O domain
O genus
O species
Chlorine gas and solid phosphorus combine to produce phosphorus trichloride gas.
Write a balanced chemical equation for this reaction.
Solid iron pellets are heated, melted and drawn into wires. This is an example of a chemical reaction.
O True
O False
Answer:
False
Explanation:
A change of state is not an example of a chemical reaction.
A chemical reaction cannot be reversed. This example however, can be. You can melt the wire down and them form it back into iron pellets
Answer:
False
Explanation:
The key to a chemical reaction is "irreversible change". If you can change it back to what it was before, it's not a chemical reaction. This is an example of a physical change.
When an object is falling, which type of energy does it continue to gain?
A. Potential
B. Kinetic
C. Atomic
D. Sound
Answer:
B Kinetic
Explanation:
Kinetic energy is the energy of a object in motion
Give the hybridization for the C in HCN
Answer:
[tex]\huge\boxed{sp \ hybridization}[/tex]
Explanation:
In HCN,
Carbon is singly - bonded ( 1 sigma bond ) to Hydrogen while triply - bonded ( 1 sigma, 2 pi bonds) to Nitrogen.
Thus, the Stearic No. for Carbons is:
= No. of sigma bonds + No. of lone pairs
= 2 + 0
= 2
According to Stearic No.:
=> sp = 2
=> sp² = 3
=> sp³ = 4
Hence,
The hybridization of C in HCN is sp.
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH1807Write balanced complete ionic equation for
CaS(aq) + CaCl2 (aq) –> CdS(s) + CaCl2 (aq).
Express your answer as a chemical equation. Identify all of the phases in your answer.
Answer:
Ca²⁺(aq) + S²⁺(aq) + Cd²⁺(aq) + 2Cl¯(aq) —> CdS (s) + Ca²⁺(aq) + 2Cl¯(aq)
Explanation:
CaS (aq) + CdCl₂ (aq) –> CdS (s) + CaCl₂ (aq)
The complete ionic equation for the above reaction can be obtained as illustrated below:
In solution:
CaS (aq) —> Ca²⁺(aq) + S²⁺(aq)
CdCl₂ (aq) —> Cd²⁺(aq) + 2Cl¯(aq)
CaS (aq) + CdCl₂ (aq) –>
Ca²⁺(aq) + S²⁺(aq) + Cd²⁺(aq) + 2Cl¯(aq) —> CdS (s) + Ca²⁺(aq) + 2Cl¯(aq)
Do Newton's Laws still apply in space?
Answer:
Yes, they work in space. I forgot an example, will edit the post when I found it
Hope this helps!
The degree of order of matter is directly proportional to the cohesive forces that hold the matter together. In other words, the more organized the state of matter, the stronger the “glue” that holds it together. Given the above which one of the states has the strongest cohesive forces?
A. Liquid
B. Solid
C. All states must have the same cohesive forces
D. Gas
Answer:
B. Solid
Explanation:
As the problem states, the stronger the cohesive forces of a substance, the more ordered that substance is.
Asking which state has the strongest cohesive forces is the same as asking which state is the most organized.
Solids are more organized than liquids (as solids have a definite shape and volume). Liquids are more organized than gases (as liquids have a definite volume).
4. How many moles of Cl2, are obtained by the
decomposition of 6.3 moles of POCI3?
Answer:
6.3moles
Explanation:
The balanced chemical equation for the decomposition of phosphorus oxychloride (POCl3) is as follows:
POCl3 → POCl + Cl2
Based on the above decomposition reaction, it shows that;
1 mol of POCl3 will decompose to give 1 mole of Cl2
Hence, 6.3 moles of POCI3 will give 6.3 moles of Cl2.
6.
List two possible hazards that occur when clients/family members smoke near oxygen.
Describe two actions the PSW could take to avoid these hazards in the workplace and
ensure their safety as well as the client's. (4 Marks)
Hazard one
Hazard two
Actions
Which two actions can people take to protect themselves during a heat
wave?
O A. Eat extra food
O B. Get plenty of exercise
C. Drink lots of water
D. Stay in the shade
Answer:
Stay in shade
Explanation:
aaaaaadffgghujollknnbcczzdfuomnb xdf
Answer:
c answer and d is correct answers
Explanation:
i hope helpful to us
how are elements classified organized?
11) A fixed amount of gas at 25.0 °C occupies a volume of 8.66 L when the pressure is 629 torr. Use
Charles's law to calculate the volume (L) the gas will occupy when the temperature is increased to
112 °C while maintaining the pressure at 629 torr.
A) 1.93
B) 38.8
C) 11.2
D) 9.26
E) 6.70
Answer:
Option C. 11.2 L
Explanation:
From the question given above, the following data were obtained:
Initial temperature (T₁) = 25.0 °C
Initial volume (V₁) = 8.66 L
Final temperature (T₂) = 112 °C
Pressure = constant
Final volume (V₂) =?
Next, we shall convert celsius temperature to Kelvin temperature. This can be obtained as follow:
T(K) = T(°C) + 273
Initial temperature (T₁) = 25 °C
Initial temperature (T₁) = 25 °C +273
Initial temperature (T₁) = 298 K
Final temperature (T₂) = 112 °C
Final temperature (T₂) = 112 °C + 273
Final temperature (T₂) = 385 K
Finally, we shall determine final volume of the gas. This can be obtained as follow:
Initial temperature (T₁) = 298 K
Initial volume (V₁) = 8.66 L
Final temperature (T₂) = 385 K
Pressure = constant
Final volume (V₂) =?
V₁/T₁ = V₂/T₂
8.66/298 = V₂/385
Cross multiply
298 × V₂ = 8.66 × 385
298 × V₂ = 3334.1
Divide both side by 298
V₂ = 3334.1 / 298
V₂ = 11.2 L
Thus, the final (i.e new) volume of the gas is 11.2 L
