Answer:
The urine may turn purple or remain colourless
Explanation:
Adding sodium hydroxide (NaOH) and hydrated copper(II) sulfate to urine in a test tube is a test for proteins in urine.
This test depends on the ability of sodium hydroxide (NaOH) and hydrated copper(II) sulfate to form purple-coloured cordination complexes with peptides. The appearance of this purple colour is a positive test for protiens in urine.
Hence, when a few drops of a mixture of sodium hydroxide and copper(ii) tetraoxosulphate (vi) solution added to a sample of urine test in a test tube, the solution may turn purple indicating the presence of proteins in urine or remain colourless indicating the absence of proteins in urine.
If you want to lower water's freezing point 18 degrees C by adding NaCl, what must the molality of the salt solution be? (K(f) for water ris 1.86 degree C/m)
Answer:
4.84 m
Explanation:
To solve this problem we need Frezing point depression.
Formula is: ΔT = Kf . m . i
ΔT = 18°C
This is data. ΔT is the difference, Freezing T° of pure solute - Freezing T° of solution.
Kf = 1.86 °C/m
m = molality. Our unknown.
i = Ions dissolved in solution, also called Van't Hoff factor.
NaCl → Na⁻ + Cl⁻
Sodium chloride can produce 2 moles of ions.
We replace data: 18°C = 1.86 °C/m . m . 2
18°C / (1.86 °C/m) . 2 = m
molality = 4.84
Why is creativity important in scientific investigations?
a. Creative solutions are often needed to solve technical problems.
b. Scientists need to creatively adjust their data to prove their hypothesis.
c. There is no way to test a hypothesis, so creativity is necessary.
d. Most scientific experiments have no data.
Answer:
a. Creative solutions are often needed to solve technical problems.
Explanation:
Science in itself is a voyage of discovery. Scientific investigators focusing on various issues are often working hard to find creative solutions to complex technical problems.
In order to find solutions to all these problems bedeviling humanity, scientific investigators must be quite creative. Creativity is always at the bedrock of finding solutions to the complex technical problems of the world which happens to be the ultimate goal of science.
Hence, creativity is indispensable in scientific investigation and creative solutions are often needed to solve technical problems.
Answer:
a. Creative solutions are often needed to solve technical problems
Explanation:
Scientific investigation is the process using the scientific method which consists of empirical techniques in obtaining answers to question raised and used for driving the investigation
The scientist carrying out the investigation into the new area, is therefore required to be creative in adapting the available resources in answering the questions based on the scientific method
In what sense are photons quantized?
A. Each photon emits more energy than its absorbs
B. Each photon can have multiple frequencies
C. Each photon travels exactly at the same speed of light
D. Each photon has a specific amount of energy
Answer:
Each photon has a specific amount of energy
Explanation:
Identify which reactants is reduced and which is oxidized .
2Au^3+(aq) + 3Cd(s) -> 2au(s) + 3Cd^2+(s)
Please help
Answer:
CD is oxidised
and
Au is reduced
hope helps u
How many grams are in 3.14 moles of PI₃?
Answer:
[tex]\boxed {\boxed {\sf 1290 \ g \ PI_3}}[/tex]
Explanation:
We want to convert from moles to grams, so we must use the molar mass.
1. Molar MassThe molar mass is the mass of 1 mole of a substance. It is the same as the atomic masses on the Periodic Table, but the units are grams per mole (g/mol) instead of atomic mass units (amu).
We are given the compound PI₃ or phosphorus triiodide. Look up the molar masses of the individual elements.
Phosphorus (P): 30.973762 g/molIodine (I): 126.9045 g/molNote that there is a subscript of 3 after the I in the formula. This means there are 3 moles of iodine in 1 mole of the compound PI₃. We should multiply iodine's molar mass by 3, then add phosphorus's molar mass.
I₃: 126.9045 * 3=380.7135 g/mol PI₃: 30.973762 + 380.7135 = 411.687262 g/mol 2. Convert Moles to GramsUse the molar mass as a ratio.
[tex]\frac {411.687262 \ g \ PI_3}{ 1 \ mol \ PI_3}[/tex]
We want to convert 3.14 moles to grams, so we multiply by that value.
[tex]3.14 \ mol \ PI_3 *\frac {411.687262 \ g \ PI_3}{ 1 \ mol \ PI_3}[/tex]
The units of moles of PI₃ cancel.
[tex]3.14 *\frac {411.687262 \ g \ PI_3}{ 1 }[/tex]
[tex]1292.698 \ g\ PI_3[/tex]
3. RoundThe original measurement of moles has 3 significant figures, so our answer must have the same. For the number we calculated, that is the tens place.
1292.698The 2 in the ones place tells us to leave the 9.
[tex]1290 \ g \ PI_3[/tex]
3.14 moles of phosphorous triiodide is approximately equal to 1290 grams of phosphorus triodide.
Why is it important for scientists to use the scientific method?
Answer:
The scientific method attempts to minimize the influence of bias or prejudice in the experimenter. Even the best-intentioned scientists can't escape bias. ... That's the job of the scientific method. It provides an objective, standardized approach to conducting experiments and, in doing so, improves their results.
Answer:
to get used to them
Explanation:
you have to practice them so that they can get into your head
What two metals are have atoms larger than that of sodium
Answer: potassium and rubidium
Explanation:
1) The group 1 of the periodic table contain six elements namely Lithium(Li), Sodium(Na),Potassium(K),Rubidium(Rb),Cesium(Cs) and Francium(Fr). These metals are called alkali metals because they form alkalies( i.e. strong bases capable of neutralizing acids) when they react with water.
2) The heavier alkali metals (K, Rb, and Cs) react so vigorously that they invariably explode.
3) This trend, which is not consistent with the relative magnitudes of the reduction potentials of the elements, serves as another example of the complex interplay of different forces and phenomena—in this case, kinetics and thermodynamics.
A gas occupies a volume of 2.50 L at a pressure of 350.0 kPa. If the temperature remains
constant, what volume would the gas occupy at 1750 kPa ?
1. 12.5 L
2. 5.00 L
3. 1.40e+2L
4. 0.500 L
Answer:
V₂ = 0.5 L
Explanation:
Given that,
Initial volume, V₁ = 2.5 L
Pressure, P₁ = 350 kPa
New pressure, P₂ = 1750 kPa
We need to find the new volume if the temperature remains constant. The mathematical relation between P and V is :
[tex]P\propto \dfrac{1}{V}\\\\or\\\\\dfrac{P_1}{P_2}=\dfrac{V_2}{V_1}[/tex]
Where
V₂ is new volume
So,
[tex]V_2=\dfrac{P_1V_1}{P_2}\\\\V_2=\dfrac{350\times 2.5}{1750}\\\\V_2=0.5\ L[/tex]
So, the new volume is equal to 0.5 L.
Mallory combines two chemicals and notices that each chemical retains its original properties. What did Mallory form?
O a mixture
a compound
an element
an atom
Answer:
A mixture
Explanation:
significant figures to 2.3 x 4.50
Answer:
10.35= 4 sig figs but change it to 2 since it's 2.3 is the lowest number
10.
hope this helps
have a good day :)
Explanation:
What is the volume of NaOH used in each Titration??
Answer:
Titration 1=33.9ml
Titration 2=33.45ml
Titration 3=33.35ml
Explanation:
Volume of NaOH used =Final reading - Initial reading
Titration 1:
Final reading =35.5ml
Initial reading=0.6ml
Volume of NaOH used =34.5ml -0.6ml=33.9ml
Titration 2:
Final reading =34.3ml
Initial reading=0.85ml
Volume of NaOH used =34.3ml -0.85ml=33.45ml
Titration 3:
Final reading =33.8ml
Initial reading=0.45ml
Volume of NaOH used =33.8ml 0.45ml=33.35ml
Hope it helps:)
In an exothermic reaction, will increasing or decreasing the reactant cause the reaction to shift towards the product?
thank you :)
B 1. What type of signal is represented by discrete values?
A analog
B continuous
C sine wave
D digital
Answer:
digital signal is the answer
PLEASE HELP!!!
Two buildings are 21m apart. The height of the taller building is 207m. The angle of depression from the top of the taller building to the top of the shorter building is 15°. Find the height of the shorter building to the nearest meter. (please try to include diagram)
Answer:
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Explanation:
How to avoid the process of corrosion?
No Links please.
I needASAP!
Answer:
5 Different Types of Corrosion Prevention Methods
Barrier Coatings. One of the easiest and cheapest ways to prevent corrosion is to use barrier coatings like paint, plastic, or powder. ...
Hot-Dip Galvanization. ...
Alloyed Steel (Stainless) ...
Cathodic Protection. ...
EonCoat.
If your end product is 1.5 moles of KMnO4, how many moles of manganese oxide were used in the reaction?
The equation for the production of potassium permanganate is as follows:
2 MnO2 + 4 KOH + O2 → 2 KMnO4 + 2 KOH + H2
You must show all work
Answer:
1.5 moles of KMnO4 will be produced from 1.5 moles of MnO2
Explanation:
The balanced equation of this chemical reaction is
2 MnO2 + 4 KOH + O2 → 2 KMnO4 + 2 KOH + H2
2 moles of MnO2 produces 2 moles of KMnO4
That means 1 moles of KMnO4 will be produced from 1 moles of MnO2
Hence, 1.5 moles of KMnO4 will be produced from 1.5 moles of MnO2
The moles of manganese oxide were used in the reaction is 1.5 moles.
What is stoichiometry?Stoichiometry of any reaction tells about the relative amount of species present before and after the chemical reaction.
Given chemical reaction is:
2MnO₂ + 4KOH + O₂ → 2KMnO₄ + 2KOH + H₂
From the stoichiometry of the reaction, it is clear that same moles of manganese oxide and potassium permanganate is involved in the reaction.
2 moles of KMnO₄ = produce by 2 moles of MnO₂
1.5 moles of KMnO₄ = produce by 2/2×1.5=1.5 moles of MnO₂
Hence, required moles are 1.5 moles.
To know more about moles, visit the below link:
https://brainly.com/question/24631381
Anyone know the answer to this one?
Answer:
C) 0.24 M
Explanation:
The given chemical reaction is presented as follows;
H₂SO₄(aq) + 2 KOH(aq) → K₂SO₄(aq) + 2 H₂O(l)
The titration experiment results are;
Volume of H₂SO₄(aq) used = 12.0 mL
Volume of KOH (aq) used = 36.0 mL
Concentration of KOH (aq) = 0.16 M
The number of moles of KOH present, n = 0.16 M × 36/1000 = 0.00576 moles
From the given reaction, 1 mole of H₂SO₄ reacts with 2 moles of KOH to give 1 mole of K₂SO₄ and 2 moles of H₂O
Therefore, 0.00576 moles of KOH reacts with (1/2) × 0.00576 moles = 0.00288 moles of H₂SO₄
Therefore, for the reaction;
The number of moles of H₂SO₄ in 12.0 mL of H₂SO₄ = 0.00288 moles
The concentration of the H₂SO₄ = 0.00288 M/(12.0 mL) = 0.24 M
The concentration of H₂SO₄ in the reaction = 0.24 M.
Help needed ASAP, I will mark your answer as brainliest.
Answer:
b
Explanation:
b
A fire is an example of an exothermic reaction. Which of the following best
supports that statement?
A. The fire is creating energy.
B. The fire is releasing energy.
C. The fire is capturing energy.
D. The fire is destroying energy.
Answer: B. Fire is releasing energy
Explanation:
Which oxide is covalent?
A. AsO2 B. K2O
C. CuO D. ZnO
Answer:
A.
Cu Zn K is are metals which form ionic bond with oxygen
what is ionic compounds??
Answer:
The ionic compounds are chemical compounds composed of ions, which is held together by electrostatic forces termed ionic bonding.
what is the ingredient formula for petroleum
Answer:
(C15H15N)
Explanation:
The diagram above shows the repeating groups of atoms that make up two samples. Will the
properties of the two samples likely be the same or different? (Examples of properties are smell,
color, and the temperature at which a substance melts.)
a
The properties will likely be different because the repeating groups of atoms that make up
each sample are different.
b
The properties will likely be different because there are more repeating groups of atoms in
Sample 2.
c
The properties will likely be the same because the repeating groups of atoms that make up
the two samples have the same number of atoms.
d
The properties will likely be the same because the repeating groups of atoms that make up
the two samples have two of the same types of atoms.
In a bakery shop, a chef bakes a cake in an electric oven. The energy outputted from the oven becomes an input to the cake system.
Which energy form is readily outputted from the oven system?
A. chemical energy
B. electrical energy
C. sound energy
D. thermal energy
URGENT!!
which has the largest London dispersion force out of the ones listed
PLS HELP NO LINKS PLS
Fill in the blank. One chlorine atom from one molecule of chlorofluorocarbon can destroy up to _____ ozone molecules.
100
100,000
10,000
50
Answer:
100,000 Ozone Molecules
Explanation:
I just found this online calculator that got the answer.
Answer:
100,000 is correct
Explanation:
(05.06 MC)
During an experiment, the percent yield of calcium chloride from a reaction was 85.22%. Theoretically, the
expected amount should have
grams What was the actual yield from this reaction? (5 points)
CaCO3 + HCI - CaCl2 + CO2 + H20
been 113
96.3 grams
О 99.0 grams
113 grams
0 121 grams
Answer:
96.3g is the actual yield from this reaction
Explanation:
Have been 113g...
The percent yield of a reaction is defined as one hundred times the ratio between actual yield (Our incognite) and the theoretical yielf (113g). The equation is:
Percent yield = 85.22% = Actual Yield / 113g * 100
0.8522 = Actual Yield / 113g
0.8522*113g =
96.3g is the actual yield from this reaction
Answer:
96.3
Explanation:
Just took the test
A group of students found metamorphic rocks near a campsite. The presence of metamorphic rock is most likely evidence of that the rock formed from .
Answer:
Igneous or sedimentary rocks.
Explanation:
The presence of metamorphic rock is most likely evidence of that the rock formed from igneous or sedimentary rocks. The igneous rock converted into metamorphic rocks when the rock experience intense heat and pressure within the Earth's crust. These metamorphic rocks are crystalline and often have a “squashed” texture. So due to high temperature and pressure, the metamorphic rock is formed from igneous rock.
The reaction of an acid and a base produce water and a
Answer:
The answer is " salt".
Explanation:
Hey there!
When any acids and base react with eachother, they forms water and respective salts.
For example:
HCl + NAOH = NACl + H2O.
Hope it helps!
A sample of hydrogen gas collected by displacement of water occupied 30mL at 24 C on a day when the barometric pressure was 736t orr. What volume would the hydrogen occupy if it were dry and at STP? The vapor pressure of water at 24 C is 22.4 torr
Answer:
[tex]v_2=6,48*10^{-4}L[/tex]
Explanation:
From the question we are told that:
Volume of hydrogen [tex]V_1=30mL=>30*10^{-3}[/tex]
Temperature [tex]T_1=24C=>24+273=>297k[/tex]
Pressure of water [tex]P_1=22.4torr=>\frac{22.4}{760}=0.0295atm[/tex]
Let
STP(Standard Temperature and pressure)
[tex]T_2=273K[/tex]
[tex]P_2=1atm[/tex]
Generally the equation for ideal gas is mathematically given by
[tex]\frac{p_1V_1}{T_1}=\frac{P_2V_2}{T_2}[/tex]
Therefore
[tex]v_2=\frac{P_1v_1T_2}{T_1P_2}[/tex]
[tex]v_2=\frac{0.0295*30*10^{-3}*273}{297*1}[/tex]
[tex]v_2=6.48*10^{-4}L[/tex] (at STP(Standard Temperature and pressure))