Answer:
Q = 319.49 J
Explanation:
Given that,
Mass, m = 16.6 g
Initial temperature, [tex]T_i=40.2^{\circ} C[/tex]
We need to find the heat needed to warm the water to 44.8 °C. The formula that is used to find the heat required is given by :
[tex]Q=mc\Delta T\\\\Q=mc(T_f-T_i)\\\\Q=16.6\ g\times 4.184\ J/g^{\circ} C\times (44.8-40.2)^{\circ} C\\\\Q=319.49\ J[/tex]
So, 319.49 J of heat is needed to warm water.
A student investigated the time taken for amylase to breakdown a 10% starch solution into glucose at
37°C. The student repeated the investigation five times
Figure 11 shows the results
time taken for amylase to produce glucose (s)
Test 4
120
125
110
115
Figure 11
() Calculate the rate of amylase enzyme activity for the 10% starch solution.
Answer:
Phenolphthalein is an indicator. It is pink in alkaline solutions and turns colourless as the pH decreases.
It can be used to measure the activity of the enzyme lipase on the breakdown of lipids.
Samples of milk containing phenolphthalein were incubated with lipase at different temperatures.
The time taken for the phenolphthalein to turn colourless was recorded and used to calculate the rate of enzyme activity.
Figure 10 shows these results.
Picture
(a) (i) Explain why phenolphthalein turns colourless when lipase breaks down the lipids in milk. (2)
(ii) Describe the effect of temperature on the activity of lipase, as shown in Figure 10. (2)
(iii) Explain why the activity of lipase changes above a temperature of 40°C. (2)
(b) A student investigated the time taken for amylase to breakdown a 10% starch solution into glucose at 37°C. The student repeated the investigation five times.
How many grams of aluminium chloride are produced when 123.2g of chlorine react with aluminium
Answer:
Mass = 154.67 g
Explanation:
Given data:
Mass of aluminum chloride produced = ?
Mass of chlorine = 123.2 g
Solution:
Chemical equation:
2Al + 3Cl₂ → 2AlCl₃
Number of moles of chlorine:
Number of moles = mass/molar mass
Number of moles = 123.2 g/ 71 g/mol
Number of moles =1.74 mol
Now we will compare the moles of aluminum chloride and chlorine.
Cl₂ : AlCl₃
3 : 2
1.74 : 2/3×1.74 = 1.16 mol
Mass of AlCl₃:
Mass = number of moles × molar mass
Mass = 1.16 mol × 133.34 g/mol
Mass = 154.67 g
Which terms are used to identify pure substances?
Answer:
mabey c or d
Explanation:
color, odor, density, melting temperature, boiling temperature, and solubility are examples of physical properties. Physical properties can be used to identify a pure substance.
In the cell, amino acid molecules combine to form
Answer:
A polypeptide chain!
Explanation:
Hopefully this helps! If this wasn't the answer you were looking for please don't hesitate to comment here or private message me! Have a nice day/night! :))
Amino acids are the fundamental building blocks of proteins. In the cell, amino acid molecules combine to form polypeptide chain or protein.
What are amino acid ?The term amino acids are defined as the building block of the protein. Amino acids are the fundamental building blocks of proteins. Their molecule contains both an amino and a carboxylic group.
Alpha-amino acids are amino acids that have an amino and a carboxyl group attached to the same carbon atom, i.e., an alpha-carbon atom. Glycine, Alanine, etc.
Proteins are made up of monomers called amino acids. A protein is composed of one or more linear chains of amino acids, each of which is referred to as a polypeptide.
Thus, In the cell, amino acid molecules combine to form polypeptide chain or protein.
To learn more about an amino acid, follow the link:
https://brainly.com/question/14583479
#SPJ2
A copper rod takes up 75 mL of space. With a density of 8.96 g/mL, what is the mass of the rod
Pleaseeesseeeeesssseredseeeesss
Answer:
B. Electrons travel through the sol
Explanation:
thats your answer :)
Mention any three ways of making salt. (please help me Asap)
A chemist titrates 100.0 mL of a 0.3065 M aniline (C6H5NH2) solution with 0.5774 solution at 25 . Calculate the pH at equivalence. The of aniline is .
Answer:
4.91
Explanation:
From the given information:
The millimoles of aniline = 100* 0.3065 = 30.65
30.65 millimoles HNO3 must be added to reach the equivalence point.
30.65 = V x 0.5774
V = 30.65/0.5774
V = 53.08 mL HNO3 must be added
Thus, total volume = 53.08 + 100 = 153.08 mL
[salt] = 30.65 / 153.08 = 0.20022 M
At equivalence point :
pOH = 1/2 [pKw + pKb + logC]
pOH = 1/2 [14 + 4.87 + log 0.20022 ]
pOH =9.086
pH = 14 - 9.086
pH = 4.914
pH ≅ 4.91 to 2 decimal places.
WILL GIVE BRANLIEST!!
Carbon tetrachloride (CCl4) is
ionic
covalent
Answer:
Covalent
Explanation:
In the carbon tetrachloride molecule, four chlorine atoms are positioned symmetrically as corners in a tetrahedral configuration joined to a central carbon atom by single covalent bonds
Answer:
Carbon tetrachloride (CCl4) is ✔ covalent.
Answers to assignment question:
What properties would you expect for CCl4? Select all that apply.
It is likely a gas or liquid at room temperature.
It is likely soluble in water.
It will likely light up a bulb in a conductivity apparatus.
It will likely have a high melting point.
Calcium oxide (CaO) is ✔ ionic.
What properties would you expect for CaO? Select all that apply.
It is likely a gas or liquid at room temperature.
It is likely soluble in water.
It will likely light up a bulb in a conductivity apparatus.
It will likely have a high melting point.
Explanation:
all correct on edge! :D
3. How many moles are in 1.49 x 1023 molecules of iodine?
Answer:
The answer is 0.25 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\ [/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{1.49 \times {10}^{23} }{6.02 \times {10}^{23} } = \frac{1.49}{6.02} \\ = 0.247508305...[/tex]
We have the final answer as
0.25 molesHope this helps you
What types of atoms typically form covalent bonds?
A. Metals with nonmetals, because their difference in electronegativity is above 1.7.
B.Metals with nonmetals, because their difference in electronegativity is below 1.7.
C.Nonmetals with nonmetals, because their difference in electronegativity is above 1.7.
D.Nonmetals with nonmetals, because their difference in electronegativity is below 1.7.
3. As a ray of white light passes through a prism, dispersion occurs. Which among the color of
the visible spectrum refracted the MOST?
C. Green
A. Yellow
B. Red
D. Violet
Your answer is option b
i.e. Red
because refractive index of red is more as compared to green, yellow and violet...
Which of the following is an example of Newton’s 2nd Law? A. A bowling ball requires more force to roll than a tennis ball B. Sitting in a chair C. A rocket blasting off D. All of the above
Answer:
The answer is A.
Explanation:
different type of flatbread
How would you ask a girl out. I know that I can use my voice, but I don’t know what to say.
Answer:
Just go out there and be yourself brother!
Explanation:
If she doesn't like you, she doesn't like the real you, therefore you don't deserve her! lol
What is the temperature of a gas if the container has a volume of 2,300 mL, with a pressure of 932 mmHg and 3.51 moles?
Answer:
The preceding temperature is equivalent to approximately 9.6 K => -263.5 °C
Explanation:
Given the provided problem, the formula may be substituted by the corresponding values:
Pressure (P)= 932 mmHg ==> 1.2 atm
Volume (V) = 2,300 mL ==> 2.31 L
Moles (n) = 3.51 moles ==> 3.51 mol
Proportional constant of ideal gas constant: (R) = 0.08206
Therefore, we can equate the following:
T= (PV)
nR
T= (1.2 atm · 2.31 L)
(3.51 mol · 0.08206)
T= 9.6 K ==> -263.5 °C
Thus, the cumulative temperature given the substituents/substance is equivalent to -263.5 °C.
Continental waters are classified into two categories Lentic and Lotic. Ecosystem has flowing waters; such as creeks, streams, rivers, springs, brooks and channels. A lentic Ecosystem has still waters such as ponds, marshes,ditches, reservoirs, and lakes. The ecosystem of Lentic and Lotic waters includes biotic (Living) interactions between plants, animals and micro- organisms, and abiotic (non living) physical and chemical interactions.
A) Fish
B) algae
C) Bacteria
D) water flow
Answer:
it is D
Explanation:
What are the parts of an electron configuration?
Answer:
Explanation:
electronic confirmation=1s^2,2S^2,2P^6,3S^2
atomic no.is 12 therefore :- this is magnesium
Period=3
Block=s-block
Group=II A
Which of the choices is an example of an element?
O CO
O Co
O C2H2O2
O CO2
Answer:
Co(cobalt) is the answer
Explanation:
Cobalt is a chemical element with the symbol Co and atomic number 27. Like nickel, cobalt is found in the Earth's crust only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal.
NEED HELP ASAP!!!!! PLEASE HELP!!!!! NEED HELP ASAP!!!!!
Directions: Name the covalent compound created.
EXAMPLE- Sr3P2= Tristrontium diphosphide
CH4 =
B2Si =
N2O5 =
CO2 =
Answer:
CH4 - Methane
B2Si - Diboron monosilicide
N2O5 - Dinitrogen pentoxide
CO2 - Carbon dioxide
Explanation:
When it comes to naming covalent compounds, there are several rules.
The name is derived based on the formula. For example, N2O5. The first element is nitrogen. To the name of the element, you add the prefix that tells us how many of its atoms are in the compound. In this case, there are two atoms, which means that the prefix will be di- (dinitrogen). The second element is oxygen. You are supposed to take only the root of the second element's name and then add the prefix denoting the number of its atoms and the suffix -ide (pentoxide). This is how we'll get dinitrogen pentoxide.
The only exception is methane (CH4), which is an organic compound. Organic compounds are named using the IUPAC nomenclature.
I GIVE BRAINLIEST TO WHO EVER GETS IT RIGHT!
which two scientist proposed an atomic model with a nucleus?
A.) Thomson
B.) Bohr
C.) Dalton
D.) Rutherford
Answer: B. Bohr and D. Rutherford
The question asks me to classify the reaction
CO2 (g)+H20(1) H2CO3 (aq)
Tubbo or TommyInnit? Choose wisely.
Answer:
Tubbo
Explanation:
more informational
:answer question number 10
Answer:
the last one
Explanation:
I'm pretty sure
Answer:
Particles on each are constantly moving (the last one)
write this number in scientific notation 41, 820, 000
Answer:
4·1×10∧-7Explanation:
[tex]\mathrm {Hey, there!}[/tex]
Let's solve your problem -
The answer to the question is 4.18 10^7.
Here is my clarification/explanation to support:
To convert a standard number to scientific notation, we have to move the decimal point up until we have a 1 digit number.
When we keep moving the decimal point, we get 4.18
Now, we will count the numbers after the 8 to get the 10 area.
There are five numbers after the 8, so we get 10^5.
Now, we will add 2 more to the 5, we get 10^7
Our answer will be: 4.18 10^7
[tex]\mathrm {Best, of, Luck!}[/tex]
Boron- 11
Atomic #
Atomic mass
# of protons
# of neutrons
# of electrons
Answer: 5 protons 6 neutrons and 5 electrons. and atomic number is 5.
Hope this helps!
Alguien me puede hacer el favor de ayudarme con estos 3 ejercicios de balanceo de ecuaciones por oxido reducción por favor 1. Fe2O3 + CO → Fe + CO2 2. Al2O3 + C + Cl2 → CO + AlCl3 3. H2S + O2 → SO2 + H2O
Answer:
1. Fe₂O₃ + 3CO → 2Fe + 3CO₂
2. Al₂O₃ + 3C + Cl₂ → 3CO + 2AlCl₃
3. 2H₂S + 3O₂ → 2SO₂ + 2H₂O
Explanation:
Para balancear ecuaciones redox se acostumbra a usar el método ion-electrón, hay que determinar qué elemento se oxida y cual se reduce lo que a la vez significa, aumento del número de oxidación o descenso del mismo.
1. Fe₂O₃ + CO → Fe + CO₂
Para este caso, el hierro se reduce, pasando de Fe³⁺ a Fe⁰ o lo que se dice estado fundamental.
Fe³⁺ + 3e⁻ → Fe
El carbono del CO se oxida a CO₂ donde el carbono pasa de C²⁺ a C⁴⁺
C²⁺ → C⁴⁺ + 2e⁻
Como los electrones quedaron desbalanceados multiplicamos por 2 y 3 las semi reacciones
(Fe³⁺ + 3e⁻ → Fe ) . 2
2Fe³⁺ + 6e⁻ → 2Fe
(C²⁺ → C⁴⁺ + 2e⁻) . 3
3C²⁺ → 3C⁴⁺ + 6e⁻
Ya podemos balancear la ecuacion final:
Fe₂O₃ + 3CO → 2Fe + 3CO₂
(como ya tenemos 2 atomos de hierro en el oxido, no haría falta agregar el 2 en la estoquiometría)
2. Al₂O₃ + C + Cl₂ → CO + AlCl₃
En este caso el carbono se oxida, y el cloro se reduce
C → C²⁺ + 2e⁻
Cl₂ + 2e⁻ → 2Cl⁻
Como el cloro es una molécula diatómica por cada cloro que se reduce, tendremos dos cloruros, tomando los 2 electrones que libera el C.
En este caso los electrones están balanceados
Al₂O₃ + C + Cl₂ → CO + 2AlCl₃
Han quedado desbalanceados el C y el O, asi que no queda otra que completar con la estequiometría
Al₂O₃ + 3C + Cl₂ → 3CO + 2AlCl₃
3. H₂S + O₂ → SO₂ + H₂O
El O₂ se está reduciendo, pasando de 0 a -2
El S del ácido se oxida de +2 a +4
O₂ + 4e⁻ → 2O⁻²
Son dos atomos de O, que cada átomo puede atrapar dos electrones, por ende, consigue enlazar 4 electrones en total
S⁺² → S⁴⁺ + 2e⁻
Como los electrones quedaron desbalanceados, completamos multiplicando la segunda semi reaccion x2
2S⁺² → 2S⁴⁺ + 4e⁻
O₂ + 4e⁻ → 2O⁻²
2H₂S + O₂ → 2SO₂ + 2H₂O
Ya que el oxigeno quedó desbalanceado en el lado producto, completamos con la estoquimetría
2H₂S + 3O₂ → 2SO₂ + 2H₂O
What is the molar mass of H2SO4?
Answer:
98.08g/mol is your answer
Explanation:
hope this helps
1. Lauri conducts an experiment to investigate how the mass of a catalyst, manganese (IV) oxide, affects the rate of production of oxygen during the decomposition of hydrogen peroxide (H2O2). Water and heat are also produced during the decomposition.
(a) (i) Name TWO factors OTHER THAN a catalyst, which can affect the rate of a chemical reaction. (2mks)
(ii) Write a balanced equation to show the decomposition of hydrogen peroxide by manganese (IV) oxide, MnO2(s) (2mks)
a)(I)the concentration of the reactants
the temperature
ii)
Chemical bonding is the combining of elementa to form
-energy levels
-atoms
-electrons
-compounds