Answer:
A. in which oxidation numbers change
Explanation:
This is because in oxidation reduction reactions or redox reactions, involves the sharing or transfer of electrons between species and the oxidation numbers changes. There is change in electrons, ions or oxidation number by gaining or lossing electrons. Increase in oxidation number is an indication of oxidation while decrease in oxidation indicate reduction.
Use the solubility rules from the Lab 4 introduction and your knowledge of qualitative separation schemes from the lab to answer the following questions. The qualitative analysis experiment you did is actually an abbreviated version of a much larger analysis scheme in which many different cations are separated and identified. Suppose a mixture contains Ag , K , NH4 , Hg22 , Pb2 , Mg2 , Sr2 , Ba2 , Cu2 , Al3 and Fe3 .
(a) Which of the following ions could you separate, by causing them to precipitate, with the addition of HCl?
Ag+ K+ NH4+
Hg22+ Pb2+ Mg2+
Sr2+ Ba2+ Cu2+
Al3+ Fe3+
(b) After the addition of HCl, the above sample is centrifuged and decanted. Which of the following cations remaining in the supernatant could you separate, by causing them to precipitate, with the addition of H2SO4? (Hint: H2SO4 is a source of sulfate ions. Select all that apply.)
Ag+ K+ NH4+
Hg22+ Pb2+ Mg2+
Sr2+ Ba2+ Cu2+
Al3+ Fe3+
Answer:
a13+a13
Explanation:
Which type of rock does Florian predict these pieces will change into when subjected to heat and pressure?
Answer:
The Florian predict the metamorphic rocks because it changes when subjected to heat and pressure.
Explanation:
i hope this helps
Which of the following is the correct decreasing order of hydrogen ions concentrations?
Answer: A> B> C > D> E
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
[tex]pH=-\log [H^+][/tex]
a) Solution A: pH =2
[tex][H^+]=10^{-2}[/tex]
b) Solution B: pH =5
[tex][H^+]=10^{-5}[/tex]
c) Solution C: pH = 7
[tex][H^+]=10^{-7}[/tex]
d) Solution D: pH = 8
[tex][H^+]=10^{-8}[/tex]
e) Solution E: pH =13
[tex][H^+]=10^{-13}[/tex]
Thus the decreasing order of hydrogen ion concentration is A> B> C > D> E
Which of this is formed when a metal reacts with steam ? *
Carbon dioxide
A Salt
An oxide
A metal hydroxide
Fill in the blanks. 3NH3
Answer:
3, 9, 3
Explanation:
The coefficient of 3 tells us that there are three molecules (the chemical unit of NH3). Each molecule of ammonia (NH3) is made up of 1 atom of nitrogen bonded to 3 atoms of hydrogen.
Since there are three molecules, we have three times the amount of atoms there are in one molecule.
3 x 1 = 3 nitrogen
3 x 3 = 9 hydrogen
1) Calculate the percent composition of each element in ammonia (NH).
Answer:
[tex]\% N=82.2\% \\\\\% H=17.8\%[/tex]
Explanation:
Hello there!
In this case, since ammonia is NH₃, we can see nitrogen weights 14.01 g/mol and hydrogen 3.03 g/mol as there is one only nitrogen atom and three hydrogen atoms; thus, the total mass is 17.04 g/mol. In such a way, the percent composition of each element turns out to be:
[tex]\% N=\frac{14.01}{17.04}*100\%=82.2\% \\\\\% H=\frac{3.03}{17.04}*100\%=17.8\%[/tex]
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Help plz now !
Which statement explains why a chemical equation must be balanced?
A. It must show the reactants and products on the correct sides of
the reaction arrow.
B. It must show that the mass of each element involved is conserved
by a chemical reaction.
C. It must show how each chemical formula is written to accurately
represent each substance.
D. It must show that coefficients and subscripts can be used in
chemical formulas.
Answer: B. It must show that the mass of each element involved is conserved by a chemical reaction.
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The correct statement why a chemical equation must be balanced is It must show that the mass of each element involved is conserved by a chemical reaction.
Answer:
B. It must show that the mass of each element involved is conserved
by a chemical reaction.
Explanation:
a p e x, just took the quiz
In the UNBALANCED chemical reaction for the combustion of acetylene (used in welding torches), determine at standard temperature and pressure, how many liters of
H2O gas are produced if 12 liters of Oxygen gas are completely consumed?
__C2H2 + __O2 —> __CO2 + __H2O
(Please help! Random answers for points will be reported)
Answer:
2 C2H2 + 5 O2 = 4 CO2 + 2 H2O
I've checked this multiple times this should be it
Joan wants to test if salt lowers the temperature at which water boils. In two or more complete sentences, describe the best way for Joan to develop a hypothesis for this situation. Write your answer in the essay box below.
Answer:
Joan's hypothesis should make a prediction about the answer to the question. A hypothesis is just an educated guess on what you think the outcome will be on the experiment. The prediction must be testable and stated in if-then form. For example, a good hypothesis for Joan's experiment could be, I think that 1/2 cup of salt will make the water boil quicker, than water without salt.
Explanation:
Hope it helped!
What is the concentration of a 22.35 L solution that contains 9.95 moles of sodium
acetate? Round your answer to the correct number of significant figures.
Answer:
0.445 M
Explanation:
Molarity = moles/Volume
M = 9.95/22.35 = 0.445 M
Which phrase describes air density?
increases as altitude increases
equals mass divided by volume
pushes molecules in one direction
exerts less pressure as it increases
If you answer I love you
Answer:B equals mass divided by volume
Explanation:I got hacks :)
Answer:
Which phrase describes air density? well b
increases as altitude increases
equals mass divided by volume
pushes molecules in one direction
exerts less pressure as it increases
Explanation:
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When a liquid is insoluble in another liquid, the liquids are said to be?
Answer:
immiscible
Explanation:
I need help with like 35 questions anyone willing to help please let me know I have discord
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Please I only have like 5 hours to complete this
Answer and Explanation:
The molar mass of a substance is all of the weights from the elements combined.
So, we have the elements
CU, S, and [tex]O_{4}[/tex]
CU has a mass is 65
S mass is 32
O has a mass of 16, but there's 4 atoms of O, so we do 16 times 4, which is 64.
Now we add.
65 + 32 + 64 is 161.
So, the answer is 160, or answer choice A.
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The type of potential energy related to an object's height
Answer:
the answer is gravitational potential energy
Answer:
Since the gravitational potential energy of an object is directly proportional to its height above the zero position, a doubling of the height will result in a doubling of the gravitational potential energy. A tripling of the height will result in a tripling of the gravitational potential energy.
Explanation:
Hope this helps?
3. Explain what would happen to the digestion process if enzymes were not present. SC.6.L.14.5
Limiting Reactant
12.0 grams of sodium reacts with 5.00 grams of chlorine. What mass of sodium
chloride could be produced?
Nas) +
Cl2(g) →
NaCls)
(1)
(2)
Identify the limiting reactant.
Determine the amount of sodium chloride produced.
Answer:
(1) Cl₂ is the limiting reactant.
(2) 8.18 g
Explanation:
2Na(s) + Cl₂(g) → 2NaCl(s)First we convert the given masses of reactants into moles, using their respective molar masses:
Na ⇒ 12.0 g ÷ 23 g/mol = 0.522 mol NaCl₂ ⇒ 5.00 g ÷ 70.9 g/mol = 0.070 mol Cl₂0.070 moles of Cl₂ would react completely with (2 * 0.070) 0.14 moles of Na. There are more Na moles than that, so Na is the reactant in excess while Cl₂ is the limiting reactant.
Then we calculate how many moles of NaCl are formed, using the limiting reactant:
0.070 mol Cl₂ * [tex]\frac{2molNaCl}{1molCl_2}[/tex] = 0.14 mol NaClFinally we convert NaCl moles into grams:
0.14 mol NaCl * 58.44 g/mol = 8.18 gHow many molecules are in 450.0 grams of aluminum fluoride(AIF3)?
Answer:
It would be exactly 5.3586262014272155. But if you were to round it up it would be 5.35.
What are the details of the chemical structure of methylisothiazolinone (MIT)?
What does this even mean? Help please and thank you!
Answer:
T₁ = P₁V₁T₂ / P₂V₂
Explanation:
The combine gas equation is given by:
P₁V₁ / T₁ = P₂V₂ / T₂
Where:
P₁ => is the initial pressure
V₁ => is the initial volume
T₁ => is the initial temperature
P₂ => is the final pressure
V₂ => is the final volume
T₂ => is the final temperature
Finally, we shall make T₁ the subject of the above expression. This can be obtained as follow:
P₁V₁ / T₁ = P₂V₂ / T₂
Cross multiply
T₁P₂V₂ = P₁V₁T₂
Divide both side by P₂V₂
T₁ = P₁V₁T₂ / P₂V₂
Thus, the formula for T₁ is:
T₁ = P₁V₁T₂ / P₂V₂
Help me please tell me and I try to make u brainliest!
Hydrogen can be produced according to the following word equation
=zinc +hydrochloric acid =zinc chloride +hydrogen [zn^+2]
Write a complete balanced chemical equation for this chemical reaction?
Answer:
Zn + 2HCl → ZnCl₂ + H₂
Explanation:
First we write the equation using the molecular formulas instead of words:
Zn + HCl → ZnCl₂ + H₂We know zinc chloride is ZnCl₂ as the problem tells us the oxidation state of zinc in the products is +2, and chloride means Cl⁻¹.
Now we proceed to balance the reaction:
There are 2 Cl atoms and 2 H atoms on the right side, so we add a coefficient of 2 to HCl on the left side:
Zn + 2HCl → ZnCl₂ + H₂Please answer by the number ! I will mark any correct answer brainliest :)
Answer:
36 joules is the answer
1/2mv^2
1/2* 8*3*3
4*9
36joules
If I began this reaction with 1.7g of O2 , how much water would I make
How do the causes of surface and deep water currents differ?
A. Surface currents are caused by wind deep water currents are caused by difference in water density
B. Surface currents are caused by the Coriolis effect deep water currents are caused by differences in water density
C. Surface currents are caused by differences in water salinity deep water currents are caused by differences in water temperature
D. Surface currents are caused by differences in water density deep water currents are caused by wind
Answer:
The answer is A. Surface currents are caused by wind deep water currents are caused by difference in water density.
What is the number of moles in 125ml of 0.25 M NaNO3solution?
Answer:
0.0313 mole.
Explanation:
From the question given above, the following data were obtained:
Volume of solution = 125 mL
Molarity of NaNO₃ = 0.25 M
Number of mole of NaNO₃ =?
Next, we shall convert 125 mL to litre (L). This can be obtained as follow:
1000 mL = 1 L
Therefore,
125 mL = 125 mL × 1 L / 1000 mL
125 mL = 0.125 L
Thus, 125 mL is equivalent to 0.125 L.
Finally, we shall determine the number of mole of NaNO₃ in the solution. This can be obtained as follow:
Volume of solution = 0.125 L.
Molarity of NaNO₃ = 0.25 M
Number of mole of NaNO₃ =?
Molarity = mole / Volume
0.25 = mole of NaNO₃ / 0.125
Cross multiply
Mole of NaNO₃ = 0.25 × 0.125
Mole of NaNO₃ = 0.0313 mole.
Which statement BEST describes why licensed health care workers are held to a higher standard?
A. They agree to ethical standards when they are licensed.
B. They agree to be good role models and always model good habits.
C. They are more involved than the public.
D. They are more educated than most of the public.
Answer:
They agree to ethical standards when they are licensed.
Explanation:
Answer:
C) They agree to ethical standards when they are licensed
Explanation:
Please help I’ll mark brainliest :)
Answer:
Biotechnology is the use of living organisms through modification to make products of technological or industrial significance.
positively, biotechnology can be used in manufacture of medicine and also synthetic forms of various hormones for use in the health and medical field.
negatively biotechnology may be manipulated for use in wars as biological warfare that can lead to loss of lives and environmental degradation
Explanation:
Answer: Biotechnology is the use of living organisms through modification to make products of technological or industrial significance.
positively, biotechnology can be used in manufacture of medicine and also synthetic forms of various hormones for use in the health and medical field.
negatively biotechnology may be manipulated for use in wars as biological warfare that can lead to loss of lives and environmental degradation
Which change represents an oxidation reaction?
One of the following is not a physical property of iron.
Mark only one oval.
malleability
magnetism
rusting
color
Answer:
Rusting
Explanation:
Rusting is oxidizing iron, which would be a chemical property.
What is the product of the equation shown?
2 Na + S203
A. Na S203
B. NaS40
C. Na2S205
D. Na2S2O3
Answer:
D
Explanation:
balancing of chemical equations