Answer:
a. absorbs energy as heat and has positive enthalpy of solution.
Explanation:
A reaction can either be exothermic or endothermic. An endothermic reaction, as the dissolution described in the question, is that which absorbs heat energy from the surroundings in order to start the reaction.
Because an endothermic reaction makes heat lost from the surroundings, the enthalpy (∆H) of the solution will be positive (+). ∆H is got by finding the difference between the enthalpy of the reactants and products and since the enthalpy of a product in endothermic reaction is more, the enthalpy change (∆T) will be positive.
How many electrons does GeH4 have
Which of the following statements is true?
A- Chemical digestion includes the physical breakdown of chunks of food.
B- Mechanical digestion begins in the mouth, and includes the tearing and grinding of food with teeth.
C- Mechanical digestion uses teeth to grind food and saliva to moisten the food
making it easier to chew.
D- Chemical digestion includes the chemical breakdown of food and mixing of the food particles with the help of the tongue
B- Mechanical digestion begins in the mouth, and includes the tearing and grinding of food with teeth.
C- Mechanical digestion uses teeth to grind food and saliva to moisten the food
making it easier to chew.
These points are true.
A sexually mature seahorse can produce thousands of offspring. What is the BEST reason overproduction of offspring by marine organisms is considered to be a reproductive advantage?
A:It increases competition.
B: It decreases competition.
C: It contributes to the organism’s biological success.
D: It causes stress on the environment which will apply stress to the creature to adapt.
How many joules of heat are needed to raise the temperature of 30.0 g of aluminum from 22°C to 80°C, if the specific heat of aluminum is 0.90 J/g°C?
Answer: There are 1566 joules of heat needed to raise the temperature of 30.0 g of aluminum from 22°C to 80°C, if the specific heat of aluminum is 0.90 J/g°C.
Explanation:
Given: Mass = 30.0 g
Specific heat = [tex]0.90 J/g^{o}C[/tex]
[tex]T_{1} = 22^{o}C[/tex]
[tex]T_{2} = 80^{o}C[/tex]
Formula used to calculate the heat energy requires is as follows.
[tex]q = m \times C \times (T_{2} - T_{1})[/tex]
where,
q = heat energy
m = mass of substance
C = specific heat capacity of substance
[tex]T_{1}[/tex] = initial temperature
[tex]T_{2}[/tex] = final temperature
Substitute the values into above formula as follows.
[tex]q = m \times C \times (T_{2} - T_{1})\\= 30.0 g \times 0.90 J/g^{o}C \times (80 - 22)^{o}C\\= 1566 J[/tex]
Thus, we can conclude that there are 1566 joules of heat needed to raise the temperature of 30.0 g of aluminum from 22°C to 80°C, if the specific heat of aluminum is 0.90 J/g°C.
. Which of these types of electromagnetic radiation has the lowest energy?
a. Radio waves
b. Visible light
c. Gamma rays
On a hot day, a 15.0 kg window increased from 20.0 degrees C to 26.7 degrees C. How much heat energy did the glass window absorb? (specific heat of glass = 0.840 J/gC)
Answer: The heat energy absorbed by glass window is 84420 J.
Explanation:
Given: Mass = 15 kg (1 kg = 1000 g) = 15000 g
Initial temperature = [tex]20^{o}C[/tex]
Final temperature = [tex]26.7^{o}C[/tex]
Specific heat capacity = [tex]0.840 J/g^{o}C[/tex]
Formula used is as follows.
[tex]q = m \times C \times (T_{2} - T_{1})[/tex]
where,
q = heat energy
m = mass of substance
C = specific heat capacity
[tex]T_{1}[/tex] = initial temperature
[tex]T_{2}[/tex] = final temperature
Substitute the values into above formula as follows.
[tex]q = m \times C \times (T_{2} - T_{1})\\ q = 15000 g \times 0.840 J/g^{o}C \times (26.7 - 20)^{o}C\\q = 84420 J[/tex]
Thus, we can conclude that the heat energy absorbed by glass window is 84420 J.
Older stars get smaller and cooler and are called white dwarfs.
True
Answer:
si
Explanation:
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What can we do to protect our oceans ?
Can u guys help me I have an f in science and this will help me a lot with my grade.
Answer:
First slide:
1) diffusion
2)water
3)high
4)low
5)balance
Second slide:
1)movement
2)without
3)energy
4)high
5)low
6)equilibrium
Final slide:
1)passive
2)energy
3)randomly
4)high
5)low
6)equilibruim
7)permeable
8)Osmosis
9)water
Hopes this helps! Good luck!
2A1 (s) + 3C12 (g) --> 2AlCl3 (s) (balanced)
When 72 grams of aluminum react, the actual yield is 125.5 grams, what is the percent yield?
i got a few mins left
Answer:
32.3%
Explanation:
Percent yield is defined as:
Actual yield (125.5g) / Theoretical Yield * 100
To find theoretical yield we have to find the moles of aluminium. As 2 moles of Al produce 2 moles of AlCl3, the moles of Al = Moles AlCl3.
With these moles we can find the mass assuming a 100% of yield (Theoretical Yield) as follows:
Moles Al = Moles AlCl3 (Molar mass Al = 26.98g/mol)
72g Al * (1mol / 26.98g) = 2.67 moles AlCl3
Mass AlCl3 (Molar mass: 133.34g/mol)
2.67 moles AlCl3 * (133.34g / mol) = 355.8g AlCl3
Percent Yield = 125.5g / 355.8g * 100 =
32.3%Una muestra de 0,830 g de MgCl2 se disuelve en 350 g de agua. Si la densidad de la disolución es 1,09 g/mL
Answer:
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J3WEFONCIONV WEJFQOMS;DX
Consider the following statements about weeding and identify the incorrect one.
a) Weeding is best done during tilling itself.
b) Weeding is the process of growing weed.
c) Weeding is the process of removal of weeds.
d) Weeding is usually done manually or by using weedicides.
Answer:
b) Weeding is the process of growing weed
Explanation:
Wedding is an agricultural process carried out to ensure maximum you won't do. It is the process by which weeds i.e. unwanted plants are removed.
As rightly stated in the question;
- Weeding is either done by manual means e.g Cutlasses or use of weedicides, which are chemicals.
- Weeding is best done during tiling operations.
The incorrect option is that "Weeding is the process of growing weed" rather it is a process of removing weed.
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Yusef is doing an experiment to find out how the amount of sunlight affects the growth of a seedling. He has three identical pots
containing grass seeds he planted at the same time. He puts them in windows that receive different amounts of sunlight each day.
Every day. Yusef looks at the pots and records his observations. What is the independent variable in Yusef's experiment?
OA type of soil
OB type of seedling
Ос.
amount of water
OD
amount of sunlight
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Answer:
asdffafAFSAfdsdf
Explanation:
4. Use the particle theory to explain density.
Answer:
Density is the total number of particles in a given volume
Explanation:
As per the particle theory, density is defined as total space occupied by certain number of particles of any given element with in a defined volume is termed as density.
Density is not the denseness of a single unit but the space occupied by many single units with in a given volume V
Hence, density is the total number of particles in a given volume.
How is stoichiometry used to calculate energy absorbed when a mass of
solid melts?
O A. Grams solid x mol/g * A Hreaction
B. Grams solid x mol/g * A Hp
C. Grams solid x mol/g * A Hfusion
O D. Grams solid x mol/g * A Hvap
Answer: Option C is correct
Grams solid x mol/g * A Hfusion
Explanation:
This is because from fusion is associated to melting and this is a process where solid particles or substances goes through transition phase and turn to liquid.
There for the stoichiometry is used to calculate energy absorbed when solid mass melt with the formula Grams solid x mol/g * A Hfusion.
Which of the following is most helpful for identifying an organism using a dichotomous key?
Its average lifespan
Its sources of food
Its habitat
Its physical structures
Answer:
Its physical structure
Explanation:
Scientist introducing a gene to the DNA of these fish that cause the fish to glow an example of which application of biotechnology?
A. Artificial selection
B. Genetic Engineering
C. cloning
D. Artificial intelligence
Answer:
The correct answer is B
Explanation:
Genetic engineering is an example of which application of because the genes are changed to get the desired features in an organism.
What is genetic engineering?Genetic engineering is the process in which we alter the genetic makeup of an organism to produce desired characterictics in that organism.
So we can conclude that Genetic engineering is an example of which application of because the genes are changed to get the desired features in an organism.
Learn more about here Genetic engineering: https://brainly.com/question/2780091
If you have 3 mol of glucose in 6 L of solution, what is the molarity of the
solution?
Answer:
0.5 M
Explanation:
Molarity = moles of solute / liters of solution
Calculate the number of moles found in 3.045x1024 atoms of helium.
PLS HELP
Explanation:
so for this u have to use this equation where
Moles = number of particle/6.02×10^23
= 3.045 × 10^24/6.02×10^23
= 5.0581
write it to 3 S.F so 5.06 moles
Convert 4.1x10^-4 moles of carbon into atoms.
Answer:
2.5×10^20atoms
Explanation:
number of moles= number of particles/Avogadro's constant
number of particles=Avogadro's constant × number of moles
number of particles=(6.02×10^23) × (4.1×10^-4)
number of particles=2.5×10^20
The tetrahedral arrangement of bonds formed by carbon and its relevance In the interaction of biomolecules
Answer:
Due to the presence of 4 valence electrons.
Explanation:
The tetrahedral arrangement of bonds formed by carbon and its relevance In the interaction of biomolecules occurs because the carbon atom has four electrons in their outermost shell and the four hydrogens has one electron each which result is a total of eight electrons distributed in four bonding orbitals making the structure of tetrahedral and the bond angles between these carbon atoms is approximately 109.5 degree.
how are living organisms in an ecosystem linked
Answer:
An environment is a local area of living creatures existing related to the nonliving segments of their current circumstance, interfacing as a framework. These biotic and abiotic segments are connected together through supplement cycles and energy streams.
Explanation:
Answer:
Living organisms require a proper, stable ecosystem/envirornment to function
Explanation:
Magnesium (used in the manufacture of light alloys) reacts with iron(III) chloride to form magnesium chloride and iron. A mixture of 41.0 g of magnesium and 175.0 g of iron(III) chloride is allowed to react. Identify the limiting reactant and determine the mass of the excess reactant present in the vessel when the reaction is complete. Select one: a. Limiting reactant is Mg; 7.4 g of FeCl3 remain. b. Limiting reactant is Mg; 46.5 g of FeCl3 remain. c. Limiting reactant is FeCl3; 1.7 g of Mg remain. d. Limiting reactant is FeCl3; 37.8 g of Mg remain. e. Limiting reactant is Mg; 134.0 g of FeCl3 remain.
Answer:
Limiting reactant is FeCl3; 1.7 g of Mg remain.
Explanation:
From the question;
The equation is;
3Mg(s) + 2FeCl₃(s) → 3MgCl₂(s) + 2Fe(s)
Amount of Mg = 41 g/24.31 g/mol = 1.687 moles
The limiting reactant yields the least amount of MgCl2
3 moles of Mg yields 3 moles of MgCl2
Hence 1.687 moles of Mg yields yields 1.687 moles of MgCl2
FeCl₃ = 175 g/162.2 g/mol = 1.0789 moles
2 moles of FeCl3 yields 3 moles of MgCl2
1.0789 moles of FeCl3 yields 1.0789 * 3/2 = 1.61835 moles of MgCl2
Hence FeCl3 is the limiting reactant
3 moles of Mg reacts with 2 moles of FeCl3
x moles of Mg reacts with 1.0789 of FeCl3
x = 3 * 1.0789 /2 = 1.61835 moles of Mg
Mass of Mg reacted = 1.61835 moles * 24.31 = 39.342 g
Mass of excess Mg = 41 g - 39.342 g = 1.7 g
How many moles of gallium chlorate, Ga(ClO3)3, must react in order to produce 674 kJ of energy according to the following reaction? 2 Ga(ClO3)3 à 2 GaCl3 + 9 O2 DH = - 130.4 kJ
Answer:
10.3 mol Ga(ClO₃)₃
Explanation:
Let's consider the following balanced thermochemical equation.
2 Ga(ClO₃)₃(s) ⇒ 2 GaCl₃(s) + 9 O₂(s) ΔH = - 130.4 kJ
According to the balanced thermochemical equation, 130.4 kJ of heat are released when 2 moles of gallium chlorate react. The number of moles of gallium chlorate that must react to produce 674 kJ of energy is:
674 kJ × 2 mol Ga(ClO₃)₃/130.4 kJ = 10.3 mol Ga(ClO₃)₃
Thermochemical equations are chemically balanced equations that take into account both the energy change and the physical states of all reactants and products. Energy is a reactant in an endothermic process, whereas it is a product in an exothermic reaction. Here the moles of Ga(ClO₃)₃ is 10.3 mol.
Let's consider the following balanced thermochemical equation.
2Ga(ClO₃)₃(s) ⇒ 2GaCl₃(s) + 9O₂(s) ΔH = - 130.4 kJ
According to the balanced thermochemical equation, 130.4 kJ of heat is released when 2 moles of gallium chlorate react. The number of moles of gallium chlorate that must react to produce 674 kJ of energy is:
674 kJ × 2 mol Ga(ClO₃)₃ / 130.4 kJ = 10.3 mol Ga(ClO₃)₃
To know more about thermochemical equation, visit;
https://brainly.com/question/10384873
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Identify the limiting reactant when 2.20 g of calcium reacts with 4.5 g of chlorine gas to produce calcium chloride. Write a balanced equation before starting.
I"LL GIVE YOU 30 POINTS AND NAME YOU BRAINLIEST IF YOU ANSWER THIS FOR MEEEEE PLZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ ITS FOR MY STUDY GUIDE!!!!!!
Answer:
2.20*4.5=?? you have to solve the multiplication ok, or its not learning
Explanation:
(Quick pls!! Just the answer, no links) Which scenario is an example of a scientific way of thinking?
A. A researcher reviews images of lunar eclipses taken by
professional photographers and then ranks them in order of which
are the most beautiful
B. A researcher writes to a government representative to convince
the representative to encourage public participation in eclipse
watching
C. A researcher analyzes data on the motions of the Moon and Earth
and then makes a prediction about when the next lunar eclipse will
ocour
D. A researcher reade several different articles on the beat way to
enjoy a lunar eclipse and then decides which method is beat
Explanation:
The right answer is C
Hope i could be helpful
Biodiversity can be altered by __________.
Select one:
All of these
a fire in the ecosystem
unexpected changes in the climate of an ecosystem
a flood in the ecosystem
A2 Could you remove the iron from the iron sulfide using
magnet?
Explain your answer.
What is the pressure of the gas if we have 3.50 moles of helium at -50.0°C
in a rigid container whose volume is 25.0 liters?
003 kPa
-58.2 kPa
259.6 kPa
0.0 kPa
Answer:
259.6kPa
Explanation:
because it is big
What is an example of Chemical energy to thermal energy to electrical current?
Answer:
Coal is burned at power plant.
Explanation:
the chemical Energy is released as coal changes
have a good day