Q. 8. Which of the following statements about plastics are true?
(i) All plastics do not have the same arrangement of monomer units.
(ii) Melamine resists fire and can tolerate heat better than other plastics.
(iii) Plastics with cross-linked monomers are also known.
(iv) Plastics have limited applications.
a) (i) and (iii) only
b) (iii) and (iv) only
c) (i), (ii) and (iii) only.
d) (i), (iii) and (iv) only
Answer:
a) (I) and (iii) only
Explanation:
Because different plastics have different size.
Thermal energy naturally flows from _________ matter to _______ matter.
Answer:
Warmer
Cooler
Explanation:
From a cross between a short-haired guinea pig (hh) and a long-haired guinea pig (Hh), what would be the possible phenotypes of the offspring?
A. 100% will have long hair.
OB. 75% will have long hair; 25% will have short hair.
OC. 50% will have long hair; 50% will have short hair.
O D. 25% will have long hair; 75% will have short hair.
Answer:
C
Explanation:
There will be a two long hair and two short hair
A sample of argon gas has a volume of 698.7l. The temp is decreased to 24.8c and the volume also decreases to 499.1l. What was the original temp
What is the molarity of a solution that contains 33.5 g of CaCl, in 600.0 mL of water.
0.503 M
O 0.0558 M
5.00 x 10-4 M
0.744 M
Water can break down to form hydrogen and oxygen gas. Balance the
equation below (hint, always balance oxygen last). What coefficients go in
the blank spaces? *
Answer:
its 2,2,1
Explanation:
What is the function of a
catalyst?
A. Build enzymes
B. Speed up chemical reactions
C. Regulate the function of an enzyme
I believe it is to speed up chemical reactions
What is the Ksp expression for the dissociation of calcium oxalate?Immersive Reader
(4 Points)
Ksp=[Ca⁺²] x [C₂O₄⁻²]
Ksp=[Ca⁺²]² x [C₂O₄⁻²]
Ksp=[Ca⁺²]⁴ x [C₂O₄⁻²]
Ksp=[Ca⁺²] x [C₂O₄⁻²]²
Answer:
Ksp = [Ca⁺²] × [C₂O₄⁻²]
Explanation:
Step 1: Write the balanced reaction for the dissociation of calcium oxalate
CaC₂O₄(s) ⇄ Ca⁺²(aq) + C₂O₄⁻²(aq)
Step 2: Write the expression for the solubility product constant (Ksp) of calcium oxalate
The solubility product constant is the equilibrium constant for the dissociation reaction, that is, it is equal to the product of the concentrations of the products raised to their stoichiometric coefficients divided by the product of the concentrations of the reactants raised to their stoichiometric coefficients. It doesn't include solids nor pure liquids because their activities are 1.
Ksp = [Ca⁺²] × [C₂O₄⁻²]
Propane is used as a fuel for camp stoves. It undergoes combustion to form carbon dioxide and water.
C3H8 + 5 02- 3 CO2 + 4H2O
How many molecules of dihydrogen monoxide will be produced from 7.328 moles of propane?
How Do i get this answer with steps ?
Answer:
1.765x10²⁵ molecules
Explanation:
C₃H₈ + 5 O₂ → 3 CO₂ + 4H₂OFirst we convert 7.328 moles of propane (C₃H₈) into moles of H₂O, using the stoichiometric coefficients of the balanced reaction:
7.328 mol C₃H₈ * [tex]\frac{4molH_2O}{1molC_3H_8}[/tex] = 29.312 mol H₂OThen we convert 29.312 moles of H₂O into molecules, using Avogadro's number:
29.312 mol * 6.023x10²³ molecules/mol = 1.765x10²⁵ moleculesA balloon can be inflated with 4.23 Liters of O2gas at STP. How much will the balloon weigh in grams?
Answer: 6.04 g
Explanation: In STP conditions, amoint of substance
n = V / Vm = 4.23 l / 22.41 l/mol = 0.188755 mol
Molar mass M(O2) = 32 g/mol and
mass m = nM
How many formula units (particles of AgNO3) are in 5.50 grams of AgNO3?
(picture for answer choices)
Answer:
No of molcules(N)= 1.98×10^22
Explanation:
m=5.5, Mm= 167, NA= 6.02×10^23
Moles(n)= m/M= N/NA
5.5/167 = N/6.02×10^23
SIMPLIFY
N=1.98×10^22molecules
The spoon's broken appearance is caused by light waves that are
A
Reflected by the glass and then absorbed the water
B
Refracted by the water
С
Absorbed by the metal spoon
D
Reflected by the metal spoon and the water
Answer:
its b
Explanation:
What is the electronegativity difference
between sodium and chlorine?
Answer: 2.23 is the difference.
Explanation: Sodium has an electronegativity of 0.93 and Chlorine has an electronegativity of 3.16, so when Sodium and Chlorine form an ionic bond, in which the chlorine takes an electron away from sodium, forming the sodium cation, Na+, and the chloride anion, Cl-.
Please help
Apply your knowledge and understanding of equilibrium constant in solving the following problems:
The equilibrium constant Kc for the reaction below is 170 at 500 K.
Determine whether the reaction mixture is at equilibrium when the concentrations of the components at this temperature are as follows:
[N2]=1.50
[H2]=1.00
[NH3]=8.00
If it is not at equilibrium, state and explain in which direction the reaction will proceed.Multi Line Text.
2()+32() ⇄ 23()
Answer:
The reaction will proceed to the right to attain the equilibrium.
Explanation:
Step 1: Write the balanced equation
2 N₂(g) + 3 H₂(g) = 2 NH₃(g)
Step 2: Calculate the reaction quotient
The reaction quotient (Qc) is calculated in the same way as the equilibrium constant (Kc) but it uses the concentrations at any time.
Qc = [NH₃]² / [N₂]² × [H₂]³
Qc = 8.00² / 1.50² × 1.00³ = 28.4
Since Qc ≠ Kc, the reaction is not at equilibrium.
Since Qc < Kc, the reaction will proceed to the right to attain the equilibrium.
Estimate the volume of a solution of 5M NaOH that must be added to adjust the pH from 4 to 9 in 100 mL of a 100 mM solution of a phosphoric acid?
Answer:
3mL of 5M NaOH must be added to adjust the pH to 7.20
Explanation:
When NaOH is added to phosphoric acid, H₃PO₄, the reaction that occurs are:
NaOH + H₃PO₄ ⇄ NaH₂PO₄ + H₂O pKa1 = 2.15
NaOH + NaH₂PO₄ ⇄ Na₂HPO₄ + H₂O pKa2 = 7.20
NaOH + Na₂HPO₄ ⇄ Na₃PO₄ + H₂O pKa3 = 12.38
We can adjust the pH at 7.20 = pKa2 if NaH₂PO₄ = Na₂HPO₄. To make that, we must convert, as first, all H₃PO₄ to NaH₂PO₄ and the half of NaH₂PO₄ to Na₂HPO₄. To solve this question we need to find the moles of phophoric acid in the initial solution. 1.5 times these moles are the moles of NaOH that must be added to fix the pH to 7.20:
Moles H₃PO₄:
100mL = 0.100L * (0.100mol / L) = 0.0100 moles H₃PO₄
Moles NaOH:
0.0100 moles H₃PO₄ * 1.5 = 0.0150 moles NaOH
Volume NaOH:
0.0150 moles NaOH * (1L / 5moles) = 3x10⁻³L 5M NaOH are required =
3mL of 5M NaOH must be added to adjust the pH to 7.203 mL of 5 Molar NaOH is required to adjust the pH of phosphoric acid.
What is pH?It is the negative log of the concentration of Hydrogen ions in the solution.
To calculate the volume of NaOH first, calculate the moles of NaOH and H₃PO₄.
Moles of H₃PO₄.
[tex]\rm moles \ of \ H_3PO_4 = 100\rm \ mL = 0.100\rm \ L \times (0.100 \ mol / L)\\\\\rm moles \ of \ H_3PO_4 = 0.01[/tex]
The moles of NaOH:
[tex]\rm Moles \ of \ NaOH =0.01 \ moles \ H_3PO_4\times 1.5 \\\\\rm Moles \ of \ NaOH= 0.0150[/tex]
The volume of NaOH:
[tex]\rm Volume\ of \ NaOH = \rm 0.0150\ moles\ NaOH \times (1 \ L / 5 \ moles) \\\\\rm Volume\ of \ NaOH = 3\times 10^{-3} L[/tex]
Therefore, 3 mL of 5 Molar NaOH is required to adjust the pH of phosphoric acid.
Learn more about pH:
https://brainly.com/question/3262317
If the plant population decreased, the amount of carbon in the atmosphere would _______.
Increase
Stay the same
Decrease
Answer:
increase answer
Explanation:
i hope that is right
For the decomposition of dinitrogen pentoxide in carbon tetrachloride solution at 30 °C , the average rate of disappearance of N2O5 over the time period from t = 0 min to t = 112 min is found to be 5.80×10^-4 M min^-1. The average rate of formation of O2 over the same time period is:__________ M min-1
Answer:
1.45 × 10⁻³ M min⁻¹
Explanation:
Step 1: Write the balanced reaction for the decomposition of dinitrogen pentoxide
2 N₂O₅(g) ⇒ 2 N₂(g) + 5 O₂(g)
Step 2: Calculate the average rate of formation of oxygen
The average rate of disappearance of N₂O₅ over the time period from t = 0 min to t = 112 min is found to be 5.80 × 10⁻⁴ M min⁻¹ (5.80 × 10⁻⁴ molN₂O₅ L⁻¹ min⁻¹). Given that the molar ratio of N₂O₅ to O₂ is 2:5, the average rate of formation of O₂ is:
5.80 × 10⁻⁴ molN₂O₅ L⁻¹ min⁻¹ × 5 molO₂/ 2 molN₂O₅ = 1.45 × 10⁻³ molO₂ L⁻¹ min⁻¹ = 1.45 × 10⁻³ M min⁻¹
A sample of liquid water at 30 c is heated until half of it boils away
Answer:
b. decreases
Explanation:
URGENT
Best answer gets Brainliest!
Mg+ 2HCI ——> MgCI2+ H2
Answer:
Reaction type: Single displacement
Reactant: Magnesium
Product: Dihydrogen - H2
How did life begin? Are we alone in the universe? What makes us human?
Answer:
This really depends on what you belive in honestly, as a christian i belive a supreme being created all but school says something happend with bacteria and evolution or something lol. If this was a serious question and you need an answer for school just search up the evolution theory
Explanation:
2 Al(s) + Fe2O3(aq) - AlO3(aq) + 2 Fe(s)
You react 20.00 grams of aluminum with iron(III) oxide. How many grams of iron should you produce?
What is the percent yield if the experimental yield is 32.67 grams of iron?
Answer:
78.8%
Explanation:
The equation of the reaction is;
2 Al(s) + Fe2O3(aq) ------> Al2O3(aq) + 2Fe(s)
Number of moles in 20g of Al= 20g/27 g/mol = 0.74 moles
From the reaction equation;
2 moles of Al yields 2 moles of Fe
0.74 moles of Al yields 0.74 moles of Fe
Hence;
Mass of Fe produced = 0.74 moles of Fe * 56 g/mol
Mass of Fe produced = 41.44 g of Fe (This is the theoretical yield of Fe)
percent yield = actual yield/ theoretical yield * 100
actual yield = 32.67 grams of iron
percent yield = 32.67 g/41.44 g * 100
percent yield = 78.8%
a. An aqueous solution of Mn(NO3)2 is very pale pink, but an aqueous solution of K4[Mn(CN)6] is deep blue. Explain why the two differ so much in the intensities of their colors.
b. Predict which of the following compounds would be colorless in aqueous solution:
a. K2[Co(NCS)4]
b. Zn(NO3)2
c. [Cu(NH3)4]Cl2
d. CdSO4
e. AgClO3
f. Cr(NO3)2
Answer:
See Explanation
Explanation:
The colour of many transition metal complexes stem from transitions of electrons between energy levels. These transitions are governed by the spin selection rules and the colour is determined by the magnitude of crystal field splitting.
According to the spin selection rules, transitions in which ΔS = 0 are forbidden. Hence, a Mn^2+high spin compound is expected to be colourless. However, contrary to the spin selection rules Mn^2+high spin compounds do exhibit transitions in which the intensity is only about one-hundredth of the intensity of the spin allowed transitions. Thus many Mn^2+ high spin compounds such as Mn(NO3)2 are very pale pink or off white.
Note also that the crystal field stabilization energy of Mn^2+ which is a d^5 low spin ion is zero hence the very pale colour observed.
K4[Mn(CN)6] is deep blue as a result of charge transfer. Also, the compound exhibits an observed crystal field stabilization energy because it is a d^5 low spin compound hence the observed colour. Its low spin nature is because the cyanide ion is a strong field ligand hence it causes a greater magnitude of crystal filed splitting.
The following compounds are colourless;
Zn(NO3)2
CdSO4
AgClO3
One thing that is common to all the compounds listed above is that they are all d^10 compounds. This means that they all possess completely filled d-orbitals hence they are colourless.
Please hurry!
*URGENT* *URGENT*
Best answer gets Brainliest!!
Please answer the question ASAP
Please someone answer this question correctly
Consider the following container with particles of a substance within it:
Lucas likes this model to use in a report but decided to add more molecules shorten the arrows and have the particles closer together. What type of matter does Lucas actually want his graphic to portray?
A) plasma
B) gas
C) liquid
D) solid
Answer:
c. liquid
Explanation:
because the are not very close if the said very closely packed together it would have been a solid
Mixed Practice:
For questions 6-9, you may not have to use your entire flow chart. Decide where to start and end using your flow chart.
4NH3 + 5O2 → 4NO + 6H2O
MM NH3 = 17.04 g/mol; MM O2 = 32 g/mol; MM NO = 30.01 g/mol; MM H2O = 18.02 g/mol
In the above reaction, how many moles of NO are formed if 824 g of NH3 react?
27.5 mol
3510 mol
48.4 mol
774 mol
Given
Mass of NO - 824 g
Molar mass of NO - 30.01g/mol
No of moles of NO = Given mass/Molar mass
No of moles of NO = 824/30.01= 27.45 mole
Hence 27.5 moles of NO are formed!
The more bonds an atom can make, the more likely it is to combine with other atoms in different ways.
Which element is most likely able to make the greatest variety of bonds?
O nitrogen
O hydrogen
O oxygen
O carbon
Answer:
carbon
Explanation:
for it has got an ideal size, neither too small nor too big
several/two grologic processes change the surface of earth quickly/gradually/over various time pirods
Answer:
sever and over
Draw the mechanism for the first step in the reaction of resorcinol with ethyl acetoacetate including all proper electron pushing arrows. Use the back of this page for space as needed.
Answer:
Attached below is the required diagram .
Explanation:
During the reaction of resorcinol and ethyl acetoacetate there is the production of a transesterification product, and this transesterification product is produced in other to increase the electrophicilty of the carbonyl center.
Attached below is the required diagram .
1. Calculate and interpret the equilibrium constant. Using the reaction below.
The equilibrium concentrations 0.60 M for E, 0.80 M for F, and 1.30 M for G. (Note: E, F, and G are all gases.) Do not include your solution.
Answer:
kc = [G]² / [E] [F], kc = [1.30M]² / [0.60M] [0.80M]
Explanation:
The reaction is:
E + F ⇄ 2G
The equilibrium constant, kc, must be written as the ratio of the molar concentrations of products over reactants. Each concentration powered to its coefficient.
For the reaction of the problem, kc is:
kc = [G]² / [E] [F]Replacing the given concentrations:
kc = [1.30M]² / [0.60M] [0.80M]Many enjoys the warm waters of a ______.
Geyser
Volcano
Hot spring
Furmarole
Tectonic
Answer:
hot spring
Explanation:
The mineral water in hot springs can also help reduce stress by relaxing tense muscles. Meanwhile as your body temperature rises in the bath, and then cools once you exit can also help you relax and fall into a deeper sleep.
A 0.682 g sample of a weak monoprotic acid, HA was dissolved in sufficient water to make 50.0 mL of solution and was titrated with a 0.135 molar NaOH solution. After the addition of 10.6 milliliters of base, a pH of 5.65 was recorded. The equivalence point was reached after the addition of 27.4 milliliters of the 0.135 molar NaOH.
a. Calculate the number of moles of acid in the original sample.
b. Calculate the molar mass of the acid HA.
c. Calculate the [H3O+] at pH = 5.65
d. Calculate the number of moles of unreacted HA remaining in solution when the pH was 5.65.
e. Calculate the value of the ionization constant, Ka, of the acid HA.
f. Calculate the value of the ionization constant, Kb, and explain how you would use it to determine the pH of a solution of a known mass of the sodium salt (Na)(A) dissolved in a known volume of water.