Answer:
to remove any remaining 2,4-dinitrophenylhydrazone
Explanation:
Usually, when an organic compound is synthesised, traces of impurities such as excess reagents or solvent remain in the product.
It is therefore imperative that these contaminants are removed so that the product can attain a very high degree of purity.
Hence, during the synthesis of 2,4-dinitrophenylhydrazone derivative, 10 mL of 2 M hydrochloric acid is titrated against the crude product so that any remaining 2,4-dinitrophenylhydrazone is removed.
HELP!!! i will give brainliest!!
Different chemical elements have different chemical symbols, and this is determined by their atomic structure. Look at the two chemical symbols in the image. Compare and contrast the atomic symbols and the atomic structure of fluorine and oxygen.
Answer:
Explanation:
fluorine have gained one electron that is why the sign is -1. they both have different number of protons. They have different neutron numbers. F have 10 and O have 8.
hope this helps :)
Define pure substance. How is it classified on the basid of chemical properties?
Answer:
if it is pure, the substances is either an element or a compound. if a substance is not chemically pure, it is either a heterogeneous mixture or a homogeneous mixture. if its composition is uniform throughout, it is a homogeneous.
Star
Planet
*
As the planet makes one completer revolution around the star, starting at the position shown the gravitational attraction between the star
and the planet will
A Continually decrease
3 Decrease, then increase
increase then decrease
Romain the same
RI
12.20 AM
618/2001
Answer:
according to the path shown in the figure it will start decreasing then again it will start increasing when the path will be nearer to the star.
Reason is gravitation force is indirectly proportional to the distance.
So, option B. decrease then increase is correct
a sample of cobalt, A, with a mass of 5.00g, is initially at 25 C. When this sample gains 6.70 J of heat, the temperature rises to 27.9 C. Another sample of cobalt, B, with a mass of 7.00 g, iw initially at 25 C. If sample B gains 5.00 J of heat, what is the final temperature of sample B
Answer:
26.5°C
Explanation:
We can solve this question using the equation:
q = m*S*ΔT
Where Q is heat gained in joules, m is the mass of the sample, S is specific heat and ΔT change in temperature.
With the sample A we can find specific heat of cobalt in order to find, in sample B, the ΔT and the final temperature:
Sample A:
q = m*S*ΔT
6.70J = 5.00g*S*(27.9°C-25.0°C)
0.462J/g°C = Specific heat of cobalt
Sample B:
q = m*S*ΔT
5.00J = 7.00g*0.462J/g°C*ΔT
1.5°C = ΔT
As the initial temperature of sample B is 25°C, final temperature is:
25°C + 1.5°C = 26.5°C
What is the Kc expression for this reaction?
2 NO(g) + O2(g) ⇌ 2 NO2(g)
a)Kc = [NO2]2 / [NO]2 [O2]
b)Kc = [NO]2 [O2] / [NO2]2
c)Kc = [NO]2 [O2] [NO2]2
d)Kc = [NO2]2 / [NO]2 + [O2]
Answer:
D
Explanation:
because product are at the top and reactant are at the bottom also it to the power of the moles in front e.g 2NO it will be to the power of 2 in this case.
hope it make sense :)
How to change τhe color of silver mercury to red???
Answer: This is the hue of mercury if you're looking for it. Mercury reacts with sulphur to generate a crimson hue. In the past, they always used a thermometer.
Explanation: However, due of its toxicity, individuals have switched to using alcohol in glass thermometers, which work similarly to mercury thermometers.
hope this helped best of luck mate! :) if this helped make sure to mark me Brainliest!
PLEASE is possible to calculate the theoretical yield without a balanced equation?
No, you absolutely need a balanced equation because you need the coefficients to figure out the molar ratios plus you need the amount of one reactant or product to determine the theoretical yield.
No, it's not possible to calculate the theoretical yield without a balanced equation.
What is the theoretical yield?Theoretical yield is the yield that is calculated by the complete reaction of the limiting reagent. This is called expected or calculated amount of product.
[tex]\rm percent\; yield = \dfrac{(actual\; yield)}{(theoretical\; yield)} \times 100\\\\[/tex]
Thus, No, it's not possible to calculate the theoretical yield without a balanced equation.
Learn more about theoretical yield
https://brainly.com/question/14966377
#SPJ2
Name an alkene that would yield the alcohol above on hydration. (Submit a single name even if there is more than one correct answer. Ignore double bond stereochemistry.) Name: fill in the blank 75a878faaf91fe7_1 2,3-Dimethylpentane . Specify whether you would use hydroboration/oxidation or oxymercuration.
Answer:
Enzyme ? ...............
Calculate the volume of 0.320-M NaOH solution needed to completely neutralize 74.0 mL of a 0.230-M solution of the monoprotic acid HBr. mL NaOH.
Answer:
53.2 mL
Explanation:
As this problem deals with the neutralization of a strong monoprotic acid and a strong base, we can solve it by using the following formula:
Ca * Va = Cb * VbWhere in this case:
Ca = 0.230 MVa = 74.0 mLCb = 0.320 MVb = ?We input the data:
0.230 M * 74.0 mL = 0.320 M * VbAnd solve for Vb:
Vb = 53.2 mLWhat's 2+7 hehdhenbeidbnejdbdbdbdi
Answer:
Answer
9......
Explanation:
Explaination:
select the two atomic models that belong to the same element !
Answer:
The second and the third atomic model.
Explanation:
An element is identified by the no. of protons in the said element. Proton number cannot be changed. Both second and third atomic model have 5 protons, so they are of the same element.
The table below provides data about a gas sample.
Volume
1.0 L
Pressure
303.9 kPa
Temperature
323 K
Which of the following can be determined using the data?
A the chemical composition of the gas
B. the condensation temperature of the gas
C. the distance between gas molecules in the sample
D. the number of gas molecules in the sample
Answer:
the number of gas molecules in the sample
molar mass of Beryllium
Answer:
The molar mass of Beryllium is 9.012182 u
what's the ph of 0.0000067 m hcl solution
Answer:
[tex]pH = - log[H {}^{ + } ] \\ = - log(0.0000067) \\ pH = 5.17[/tex]
How many grams of carbon atoms are present in a sample of C3H8 if there are 4.70 moles of hydrogen atoms in the sample
Answer:
21.12 grams
Explanation:
Using the given number of hydrogen moles, we calculate the number of carbon atoms, keeping in mind that there are 3 carbon moles per hydrogen mol:
4.70 mol H * [tex]\frac{3molC}{8molH}[/tex] = 1.76 mol C
Finally we convert 1.76 moles of carbon into grams, using its molar mass:
1.76 mol * 12 g/mol = 21.12 g
4. Cuanto electrones se necesitan para
pesarlo mismo que un proton?
Answer:
aproximadamente dos mil
Explanation:
masa_proton/masa_electron=
1.673e-24 / 9.11e-28 = 1836.443468715697
Read the given equation:
NH + HCI - NH4ACI
Which of the following is true about the equation?
NH3 is the acid and NH4Cl is the salt.
NH3 is the base and NH4Cl is the salt.
HCI is the acid and NH3 is the salt.
HCl is the base and NH3 is the salt.
Answer:
NH3 is the base and NH4Cl is the salt.
Explanation:
Hello there!
In this case, according to the given information, it is possible for us to rewrite the chemical equation and thus obtain:
[tex]NH_3+HCl\rightarrow NH_4Cl[/tex]
Whereas it is possible to notice that ammonia, NH3, received the hydrogen ions from HCl to form NH4 ions and Cl ions; in such a way, we infer that NH3 is the base and NH4Cl is the salt.
Regards!
Answer:
NH3 is the base and NH4Cl is the salt
Explanation:
Determine the mass in grams of hydrogen gas produced if 40.08 g of calcium react with excess aqueous hydrogen phosphate.
Answer:
[tex]2.02gH_2[/tex]
Explanation:
Hello there!
In this case, according to the given information, it turns out possible for us to to calculate the mass of hydrogen gas by firstly setting up the undergoing chemical reaction:
[tex]2H_3PO_4+3Ca\rightarrow Ca_3(PO_4)_2+3H_2[/tex]
Thus, we apply the following stoichiometric setup, whereas the atomic mass of calcium is 40.08 g/mol, that of hydrogen is 2.02 g/mol and the mole ratio of these two substances is 3:3:
[tex]40.08gCa*\frac{1molCa}{40.08gCa}*\frac{3molH_2}{3molCa}*\frac{2.02gH_2}{1molH_2} \\\\=2.02gH_2[/tex]
Regards!
..........................
In the presence of excess iodide ions, the iodine formed by reaction of iodide with NBS will react further to form triiodide ions. What does the triiodide combine with to form the blue color of the endpoint
Answer:
Starch.
Explanation:
When the triiodide combine with starch, it forms dark blue colour. Amylose in starch is responsible for the occurrence of a deep blue color when the iodine is combine with the starch. The iodine molecule goes inside of the amylose coil which makes a linear triiodide ion complex that goes into the coil of the starch that leads to an intense blue-black color in the end so we can say that starch turns the colour into blue.
Which is an example of poor safety practices when working outdoors
Answer:
C
Explanation:
u can't touch a chemical with bare skin
Answer:
touching a chemical with his or her bare skin.
Which expression gives the standard enthalpy
change of formation for methanol?
Answer:
25
Explanation:
bec
Match the following parts of an atom to their description.
Neutron
?
Negatively charged
particle that moves
around the nucleus
Nucleus
?
Positively charged particle
in the nucleus
Electron
2
Noncharged particle in the
nucleus
Proton
?
Composed of protons and
neutrons
Answer:
Neutron - non charged particle in nucleus
nucleus - composed of proton and Neutron
electron - negatively charged particle that moves around the nucleus
proton - positively charged particle in the nucleus.
Explanation:
these the are definitions of the terms
For the reaction...
N2 + O2 <=> 2NO: AH = +182 kJ mol-1.
If the temperature is increased the equilibrium position will shift
Your answer:
a) to the left
b) to the right
c) to the left and right
d) neither left nor
right
Answer:
B
Explanation:
AH is positive so the forward reaction is endothermic. Thus, increasing temperature would cause equilibrium to shift to the right as endothermic reaction favors higher temperature. This increases the yield of NO.
Who at the top of the food web
Answer and Explanation:
Humans are one of the organisms at the top of a food web. Other animals are Orcas, Lions, Raptors, and others. These animals are called Ape.x Predators, because they are at the top of the food web.
#teamtrees #PAW (Plant And Water)
How is the enthalpy of reaction shown in this potential energy diagram
Answer:
In the given potential energy diagram, the energy of product at higher level and energy of reactant at lower level. The for this reaction will be positive. So, the enthalpy of reaction is defined as the difference of the energy of the reactants and the energy of the products.Hope this is fine for you,,!what will happen if atom hit earth with speed of light?
Answer:
A little atom will leave a big hole and a big atom cant travel that fast
Explanation:
How many carbon dioxide molecules react to form one glucose molecule during photosynthesis
Answer:
6 molecules
Explanation:
Only three elements are present in the products of photosynthesis: oxygen, carbon, and hydrogen. These same elements are present in the reactants of photosynthesis. Notice that it takes six molecules of water and six molecules of carbon dioxide to make one molecule of glucose
Answer:
6 molecules of carbone dioxide.
What determines the ending units of a stoichiometry problem?
Answer:
1.Write the balanced chemical equation.
2.Convert the units of the given substance (A) to moles.
3.Use the mole ratio to calculate the moles of wanted substance (B).
4.Convert moles of the wanted substance to the desired units.
Explanation:
A student sets up the following equation to convert a measurement.
(The stands for a number the student is going to calculate.)
Fill in the missing part of this equation.
Answer:
–0.13 Pa.m²
Explanation:
From the question given above, the following data were obtained:
Measurement (Pa.mm²) = –1.3×10⁵ Pa.mm²
Measurement (Pa.m²) =?
We can convert from Pa.mm² to Pa.m² by doing the following:
1 Pa.mm² = 1×10¯⁶ Pa.m²
Therefore,
–1.3×10⁵ Pa.mm² = –1.3×10⁵ Pa.mm² × 1×10¯⁶ Pa.m² / 1 Pa.mm²
–1.3×10⁵ Pa.mm² = –0.13 Pa.m²
Thus, –1.3×10⁵ Pa.mm² is equivalent to –0.13 Pa.m².
The complete equation will be:
[tex](-1.3\times 10^5 Pa.mm^2)\times 10^{-6}=(-0.13) Pa.m^2[/tex]
Explanation:
Given:
The equation to convert a measurement:
[tex](-1.3\times 10^5 Pa.mm^2)\times ? = ? Pa.m^2[/tex]
To find:
The missing part of the equation.
Solution:
[tex](-1.3\times 10^5 Pa.mm^2)\times ? = ? Pa.m^2[/tex]
On LHS the unit is in [tex]Pa. mm^2[/tex] and RHS the unit is in [tex]Pa.m^2[/tex] which means that we have to convert [tex]mm^2[/tex] to [tex]m^2[/tex]
In 1 millimeter there are 0.001 meters.
[tex]1 mm = 0.001 m\\1 mm^2=0.000001 m^2=10^{-6} m^2[/tex]
So, the complete equation will be:
[tex](-1.3\times 10^5 Pa.mm^2)\times 10^{-6}=(-0.13) Pa.m^2[/tex]
Learn more about conversions here:
brainly.com/question/24530464
brainly.com/question/17743460
