Answer:
potassium cyanide
Explanation:
while eye medications do harm your immune system it is not enough to kill someone. criminals mainly used potassium cyanide because it was cheap. it serves as a substitute for ethanol.
A 25.0 mL NaOH solution of unknown concentration was titrated with a 0.189 M HCl solution. 19.6 mL HCl was required to reach the equivalence point. In a separate titration, a 10.0 mL H3PO4 solution was titrated with the same NaOH solution. This time, 34.9 mL NaOH was required to reach the equivalence point. What is the concentration of the H3PO4 solution
Answer:
0.172 M
Explanation:
The reaction for the first titration is:
HCl + NaOH → NaCl + H₂OFirst we calculate how many HCl moles reacted, using the given concentration and volume:
19.6 mL * 0.189 M = 3.704 mmol HClAs one HCl mol reacts with one NaOH mol, there are 3.704 NaOH mmoles in 25.0 mL of solution. With that in mind we determine the NaOH solution concentration:
3.704 mmol / 25.0 mL = 0.148 MAs for the second titration:
H₃PO₄ + 3NaOH → Na₃PO₄ + 3H₂OWe determine how many NaOH moles reacted:
34.9 mL * 0.148 M = 5.165 mmol NaOHThen we convert NaOH moles into H₃PO₄ moles, using the stoichiometric coefficients:
5.165 mmol NaOH * [tex]\frac{1mmolH_3PO_4}{3mmolNaOH}[/tex] = 1.722 mmol H₃PO₄Finally we determine the H₃PO₄ solution concentration:
1.722 mmol / 10.0 mL = 0.172 Mhow many moles of an NH3 can be produced from 2.82 moles of nitrogen in the following reaction:
1) Heat is the ______ of energy and a unit is ____.
A: Measure; Joule
B: Measure; Kelvin
C: Movement; Kelvin
D: Movement; Joule
2) ______ is the internal energy of particles and when this motion is measured, the unit used is ___.
A: Heat; Joule
B: Thermal Energy; Kelvin
C: Thermal Energy; Joule
D: Heat; Kelvin
Answer:
Q1) B
Q2) C
Kelvin is the SI unit of temperature.
which solution has a higher percent ionization of the acid , a .10 M solution of HC2H3O2 (aw) or a .010 M solution of HC2H3O2(aq)
Answer:
0.0010 M of HC2H302(aq)
HOW MANY MOLES OF CS2 FORMS WHEN 2.7 MOLE C REACTS
A sample of polonium-210 has an initial mass of 390 milligrams (mg). If the half-life of polonium-210 is 36 days, how many mg of the sample remains after 36 days?
A.
48.75 mg
B.
392 mg
C.
97.5 mg
D.
195 mg
Answer:
d
Explanation:
9. A student is dissolving sugar in water. What can
the student do to make the sugar dissolve faster?
A. Nothing, sugar will not dissolve in water
B. Add more water.
C. Add ice to the water.
D. Stir the solution.
Answer:
D
Explanation:
Sugar will dissolve faster when you stir the solution quickly because the act of stirring increases kinetic energy which increases the temperature.
name the process which takes place when propene gas molecules are converted into a giant molecule
Answer:
Polymerization, any process in which relatively small molecules, called monomers, combine chemically to produce a very large chainlike or network molecule, called a polymer. The monomer molecules may be all alike, or they may represent two, three, or more different compounds.
Introduction: Reaction rates are also influenced by surface area and concentration. The surface area of a solid is a measure of how much of the solid is exposed to other substances. The concentration of a substance is a measure of how many molecules of that substance are present in a given volume. Question: How do surface area and concentration affect reaction rates
Answer:
See explanation
Explanation:
Surface area has to do with the number of solid particles that are exposed at a given time and is capable of colliding with other reactant particles. When more surface area is exposed for reaction, then it means that more particles are likely to collide with each other leading to faster chemical reaction rates. When few particles are exposed for reaction (low surface area) then less collisions occur and the rate of reaction is decreased.
Similarly, concentration refers to the amount of substance present. The greater the amount of substance present, the greater the likelihood of collision between particles and the greater the rate of reaction and vice versa.
The more energy that particles have, the ___ they move.
The more energy that particles have, the more they move.
how real gases differ from ideal gases?
An ideal gas is one that follows the gas laws at all conditions of temperature and pressure. To do so, the gas would need to completely abide by the kinetic-molecular theory. On the other hand, a real gas is a gas that does not behave according to the assumptions of the kinetic-molecular theory.
Furthermore, the particles of an ideal gas are extremely small and have a mass equivalent to practically zero. Ideal gas particles also have no volume.
An example of a real gas is helium, oxygen, and nitrogen.
When NH3(g) reacts with O2(g) to form N2O(g) and H2O(l) , 342 kJ of energy are evolved for each mole of NH3(g) that reacts. Write a balanced thermochemical equation for the reaction with an energy term in kJ as part of the equation. Note that the answer box for the energy term is case sensitive. Use the SMALLEST INTEGER coefficients possible and put the energy term (including the units) in the last box on the appropriate side of the equation. If a box is not needed, leave it blank.
Answer:
2 NH₃(g) + 2 O₂(g) ⇒ N₂O(g) + 3 H₂O(l) ΔH° = -684 kJ
Explanation:
Let's consider the unbalanced equation that occurs when NH₃(g) reacts with O₂(g) to form N₂O(g) and H₂O(l).
NH₃(g) + O₂(g) ⇒ N₂O(g) + H₂O(l)
We will begin balancing N atoms by multiplying NH₃(g) by 2.
2 NH₃(g) + O₂(g) ⇒ N₂O(g) + H₂O(l)
Then, we will balance H atoms by multiplying H₂O(l) by 3.
2 NH₃(g) + O₂(g) ⇒ N₂O(g) + 3 H₂O(l)
Finally, we will get the balanced equation by multiplying O₂(g) by 2.
2 NH₃(g) + 2 O₂(g) ⇒ N₂O(g) + 3 H₂O(l)
Since 342 kJ of energy are evolved for each mole of NH₃(g), and there are 2 moles of NH₃(g) in the balanced equation, the heat evolved will be2 × 342 kJ = 684 kJ. By convention, when heat is evolved, it takes a negative sign. The balanced thermochemical equation is:
2 NH₃(g) + 2 O₂(g) ⇒ N₂O(g) + 3 H₂O(l) ΔH° = -684 kJ
A sample of polonium-210 has an initial mass of 390 milligrams (mg). If the half-life of polonium-210 is 36 days, how many mg of the sample remains after 72 days?
A.
392 mg
B.
195 mg
C.
97.5 mg
D.
48.75 mg
Answer: D. 48.75
Explanation: just took the test
Answer:
D
Explanation:
I got this question right on my test.
t-Butyl alcohol was produced by the liquid-phase hydration (using water, W) of isobutene (I) over an Amberlyst-15 catalyst.
a. True
b. False
Answer:
True
Explanation:
This is because, The hydroboration oxidation of an alkene which is isobutene in the presence of a catalyst will result to alcohol as the product . Therefore, the OH group will attach or link itself to the carbon which is less obstructed. Thus this reaction is in accordance to Anti-Markownikoff's rule.
So isobutene on hydroboration oxidation will produce ter isobutyl alcohol.
In both industry and research there are often times when one particular component of a mixture needs to be separated from a solution. Maybe it is a rare metal that is dissolved in a mixture of minerals. Maybe it is a particular protein from lysed plant cells. If the desired component is volatile, distillation could be used. But if the goal is to separate ions in solution, fractional precipitation is preferred.
a. True
b. False
Answer:
a. True
Explanation:
Distillation process is a process that is used to separate the components or the substances from the liquid mixtures by using selectively boiling and condensation.
While fractional precipitation is a process which separates the ions from solution based on the different solubilities.
Therefore, the answer is true.
Which is the function of the organ shown below
Answer:
c the pancreas produce enzyme that breakdown carbohydrate protein and fat
Mechanical digestion begins in the_____ and involves physical processes, such as chewing.
Answer:
begins in the mouth
16. Given the unbalanced equation:
_Al + CuSO4 → _A1,(SO2), + --Cu
When the equation is balanced using
the smallest whole-number coefficients,
what is the coefficient of AI?
(1) 1 (2) 2 (3) 3
(4) 4
Explanation:
Consider matrix A.
What is the inverse of A? Fill in the missing elements in the matrixs.Consider matrix A.
What is the inverse of A? Fill in the missing elements in the matrixs.
(2) 2.
Explanation:
2Al + 3CuSO4 → Al2(SO4)3 + 3Cu
Hence, now yet it's balanced chemical equation.
How to pass chem!!!!!!!!!!
Answer:
refer to below
Explanation:
- read your textbook! especially the topics that are most confusing
- as you read, make sure to take notes/make an outline. write the words from the text in your own words. In chem, the textbook explanations are usually very detailed, so putting it in your own words will help you remember and understand what you write.
- make sure you really understand the concepts. don't just memorize what you read.
- draw diagrams and structures. seeing how things are structured will help you visualize what you learn
- ask questions to your teacher. if there is anything confusing, make sure to refer to your teacher as they will hopefully be able to explain it so it won't be confusing
These tips have helped me pass chem with an A. Hope all of this helped!
Answer:
Explanation:
Study material, ask for help, read textbook and do practice problems, get a tutor, beg your teacher for marks,
A 35 Liter tank of Oxygen is at 315 K with an internal pressure of 190 atmospheres. How many moles of gas does the tank contain?
A compound containing phosphorus and oxygen has a molar mass of 157.9 g/mol and an empirical formula of PO3 .
Answer: The molecular formula of the compound is [tex]P_2O_6[/tex]
Explanation:
The molecular formula is the chemical formula that tells about the number of atoms of each element present in a compound. Molecular formula and empirical formula can also be the same when the number of atoms is in the simplest whole-number ratio.
To calculate the molecular formula, the number of atoms of the empirical formula is multiplied by a factor known as valency that is represented by the symbol, 'n'.
[tex]n=\frac{\text{Molecular mass}}{\text{Empirical mass}}[/tex] ...(1)
Given empirical formula is [tex]PO_3[/tex]
Empirical mass = [tex][(1\times 30.97) + (3\times 15.99)]=78.94 g/mol[/tex]
Molecular mass = 157.9 g/mol
Plugging values in equation 1:
[tex]n=\frac{157.9 g/mol}{78.94g/mol}\\\\n=2[/tex]
Molecular formula of the compound becomes [tex]P_{2\times 1}O_{2\times 3}=P_2O_6[/tex]
Hence, the molecular formula of the compound is [tex]P_2O_6[/tex]
What is the wavelength of a photon with an energy of 3.26 x 10-19 J?
A. 527 nm
B. 610 nm
C. 492 nm
D. 671 nm
Answer:
610 nm
Explanation:
Apx
What is the mass of 4.76 moles of Na3Po4?
SHOW WORK PLEASE - NO LINKS OR FILES(I will not open them)
( btw if you sent a link do not answer , I have already reported your accounts )
Answer:
780.354g
Explanation:
22.99(3)+30.97+16(4)
=163.94g/mol
163.94*4.76=780.354g...
What is the volume, in liters, of 0.350 mol of nitrogen gas at 32°C and
0.980 atm of pressure? *
A. 9.85 L
B. 8.94 L
C. 104.6 L
D. 0.94 L
Answer: The volume is 8.94 L.
Explanation:
Given: no. of moles = 0.350 mol, Pressure = 0.980 atm
Temperature = [tex]32^{o}C = (32 + 273) K = 305 K[/tex]
Formula used to calculate the volume is as follows.
PV = nRT
where,
P = pressure
V = volume
n = number of moles
R = gas constant = 0.0821 L atm/mol K
T = temperature
Substitute the values into above formula as follows.
[tex]PV = nRT\\0.980 atm \times V = 0.350 mol \times 0.0821 L atm/mol K \times 305 K\\V = 8.94 L[/tex]
Thus, we can conclude that the volume is 8.94 L.
Calculate the specific heat capacity for bone based on the above data. Show your work.
Answer:
What above data?
Explanation:
There is no data to be seen here.
CH4 +2H2S = CS2+ 4H2
If the reaction shifts to the right what are the products?
If the reaction shifts to the right, which chemicals decrease in The process?
If the reaction shifts to the left what are the products?
If the reaction shifts to the left, which chemicals decrease in the process?
I need the correct answers
Answer:
Acids: Tastes Sour
Has a ph less than 7
Base: Bitter
Has a ph greater than 7
slippery
Acid&Base: Conducts electricity
What is the oxidation state of S in S2O32−?
A. +3 B. +2 C. –2 D. +4
Answer:
it'd be +2
Explanation:
Since 3 atoms of oxygen are present, so its combined oxidation number will be3(−2)=−6. Now this ion contains a charge of−2, where the sum of the oxidation number of all atoms in an atom is equal to−2. So the oxidation number of S in S2O2−3 should be +2.
Why are some chemical substances, like oil and coal, considered nonrenewable?
the process that forms them stops working after a decade
the process that forms them has not worked for millions of years
the process that forms them is very fast
the process that forms them is very slow
Answer:
The process of the formation of coal and oil is a very gradual and slow process.
Explanation:
The process of the formation of coal and oil is a very gradual process that takes up to millions of years.
The object shown is made of glass. What is it called?
Answer: prism
Explanation: A prism is a polyhedron, with two parallel faces called bases. The other faces are always parallelograms. The prism is named by the shape of its base.
