Answer: answer for the 1st one In a reactivity series, the most reactive element is placed at the top and the least reactive element at the bottom. More reactive metals have a greater tendency to lose electrons and form positive ions . answer for the 2nd one Food packaging is of high societal value because it conserves and protects food, makes food transportable and conveys information to consumers. It is also relevant for marketing, which is of economic significance. answer for the 3rd one Aluminium is a highly reactive metal, yet it is used to make utensils for cooking. ... This is because aluminium reacts with oxygen present in air to form a thin layer of aluminium oxide. This oxide layer is very stable and prevents further reaction of aluminium with oxygen.
Explanation:
Please mark me brainliest I tried so hard and I know it’s correct pls
How many pili are in a bacterial cell
Answer: Bacterial species where observed Typical number on cell Distribution on cell surface
Escherichia coli (common pili or Type 1 fimbriae) 100-200 uniform
Neisseria gonorrhoeae 100-200 uniform
Streptococcus pyogenes (fimbriae plus the M-protein) ? uniform
Pseudomonas aeruginosa 10-20 polar
Explanation:
Pili are structures that extend from the surface of some bacterial cells.
These are hollow, non-helical, filamentous appendages.
Hope it helps you
Substance
Number of Protons
Number of
Electrons
2.
3
lithium
fluorine
9
10
19
potassium
sulfur
19
18
16
19. Which substance is electrically neutral?
A. lithium
B. fluorine
Β
C. potassium
D. sulfur
20. Which substance has an overall I'charge?
Answer:
lithium 3
Explanation:
This is because lithium has three protons
This unit describes volume, and may be used to describe liquids or gases.
O A. Meter
O B. Liter
O C. Gram
O D. Mole
Answer: aaaaaaaaaaa
The basic SI unit for volume is the cubic meter (m3), but smaller volumes may be measured in cm3, and liquids may be measured in liters (L) or milliliters (mL).
Explanation:
How many atoms are in 54.4 g of carbon-12?
Answer:
12.00 g C-12 = 1 mol C-12 atoms = 6.022 × 1023 atoms • The number of particles in 1 mole is called Avogadro's Number (6.0221421 x 1023).
Explanation:
carry on learning
(S)-3-Methylhexane undergoes radical bromination to yield optically inactive 3-bromo-3-methylhexane as the major product. Is the product chiral
Answer:
No, the product is not chiral
Explanation:
The compound (S)-3-Methylhexane is chiral. However, the bromination of this compound via free radical mechanism yields an achiral intermediate as shown in the image attached to this answer.
This achiral intermediate is a flat and planar tertiary radical. Attack on either face of this radical specie is possible. This leads us to obtain a 50-50 mixture of (R) and (S) - 3-bromo-3-methylhexane.
This is a racemic mixture hence it is optically inactive.
What is exactly the pH value of distilled water?
Which of the following is an example of a natural polymer?
a) Wool
Ob) Super Glue
c) Nylon
d) Teflon
please hurry
Answer:
A
Explanation:
because it occurs in nature and all other option are synthesis.
propanoyl chloride reacts with LiAlH4, what will be the product
liquid mass has a volume of 9.2 and density of 0.75
Answer:
6.9
Explanation:
Mass(m)=?
Density (D)=0.75
Volume (v)=9.2
M=D×V
M=0.75×9.2
M=6.9
Use the following balanced equation to answer the questions below.
3. What do you call the process by which humans extracts stones fron the mountains for
construaction purposes
For each of the scenarios, determine if the ionic strength of the solution would increase, decrease, or not change. Ignore any effects caused by the change in volume.
1) If a solution of HNO3 were added to a solution of KOH , the ionic strength of the KOH solution would:_____.
A. Increase.
B. Decrease.
C. Not change.
2) If a dilute solution of KOH were added to a solution of CaCl2 (Ca(OH)2 (s) is formed), the ionic strength would:____.
A. Increase.
B. Decrease.
C. Not change.
3) If a dilute solution of benzoic acid were titrated with a solution of KOH the ionic strength would:____.
4) If a solution of NaOH were added to a solution of iron(II) chloride, the ionic strength would:____. A. Increase.
B. Decrease.
C. Not change.
Answer:
1) increases
2) decrease
3) increase
4) decrease
Explanation:
When ionic compounds dissolve in water, the concentration of ions in solution increases since ionic substances dissociate into ions in solution. The greater the concentration of ions in a solution, the greater the ionic strength of that solution.
Hence, if HNO3 is added to KOH solution, the ionic strength of the solution is increased due to an increase in the number of ions in the solution.
Also, when benzoic acid is titrated against KOH, potassium benzoate (an ionic substance) is formed thereby increasing the ionic strength of the solution.
However, when KOH is added to CaCl2, a precipitate (Ca(OH)2) is formed. Also, when NaOH is added to FeCl2, a precipitate (Fe(OH)2) is formed. In both cases, the formation of the precipitate decreases the concentration of ions in the solution thereby decreasing the ionic strength of the solution.
If one of your samples had a mass of 25.62 g and a volume of 21.9 cm3, would this sample also be the same material you have been working with
Answer:
If the density of the material is equal to the density of the material you have been working with it is possible that the samples are the samples
Explanation:
Density is an intensive property of the matter (Doesn't depends of its amount) that is widely used to identify a substance. Density is the ratio between the mass of the substance (In this case 25.62g) and the volume this amount occupies (21.9cm³). The density is:
25.62g / 21.9cm³ =
1.17g/cm³.
If the density of the material is equal to the density of the material you have been working with it is possible that the samples are the samplesA pure copper cube has an edge length of 1.76 cm. How many copper atoms does it contain? (volume of a cube = (edge length)^3; density of copper = 8.96 g/cm^3 )
How many atoms are there in 5.8 mol of iron
6CO2 + 6H20 --> C6H12O6 + 602
What is the total number of moles of CO2 needed to make 2 moles of CH1206?
Answer:
12 mol CO₂
General Formulas and Concepts:
Atomic Structure
CompoundsMolesMole RatioStoichiometry
Analyzing reactions rxnUsing Dimensional AnalysisExplanation:
Step 1: Define
Identify
[rxn] 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
[Given] 2 mol C₆H₁₂O₆
[Solve] mol CO₂
Step 2: Identify Conversions
[rxn] 6CO₂ → C₆H₁₂O₆
Step 3: Convert
[DA] Set up: [tex]\displaystyle 2 \ mol \ C_6H_{12}O_6(\frac{6 \ mol \ CO_2}{1 \ mol \ C_6H_{12}O_6})[/tex][DA] Multiply [Cancel out units]: [tex]\displaystyle 12 \ mol \ CO_2[/tex]Based on the nature of the reactants in each of the equations below, which reaction at 25°C will occur at the fastest rate?
A
C(s) + O2(g) + CO2 (g)
B
NaOH(aq) + HCl(aq) + NaCl(aq) + H2O(l)
C.
CH3OH( 2) + CH3COOH(e) → CH3COOCH3 (aq) + H2O(l)
D.
CaCO3(s) - CaO(s) + CO2 (g)
Based on the nature of the reactants in each of the equations below, which reaction at 25°C will occur at the fastest rate will be-
NaOH + HCl = NaCl + H₂O and the correct option is option B.
What is reaction rate?The rate of reaction or reaction rate is the speed at which reactants are converted into products. When we talk about chemical reactions, it is a given fact that rate at which they occur varies by a great deal.
Some chemical reactions are nearly instantaneous, while others usually take some time to reach the final equilibrium.
Increasing the surface area of one or more reactants affect the reaction rate of a system will speed up the reaction.
increase the concentration of a reactant will usually speed the reaction rate of a chemical system.
Therefore, based on the nature of the reactants in each of the equations below, which reaction at 25°C will occur at the fastest rate will be-
NaOH + HCl = NaCl + H₂O and the correct option is option B.
Learn more about Reaction rate, here:
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Northern cod produce proteins that protect their cells from damage caused by subzero temperatures. Measurements of the osmotic pressure for two "antifreeze" proteins at 18°C yielded the data listed below. Use this information to calculate the molar mass for each of the proteins. Assume these proteins are nonelectrolytes and use the value i = 1.
Required:
If a 54.1 mg sample of protein A in 1.5 mL of water has an osmotic pressure of 0.285 atm, what is the molar mass of protein A?
Answer: The molar mass of protein A is 3023.41 g/mol.
Explanation:
To calculate the osmotic pressure, we use the formula:
[tex]\pi=i\times M\times R\times T[/tex]
OR
[tex]\pi=i\times \frac{\text{Given mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution}}\times R\times T[/tex] .....(1)
Where,
[tex]\pi[/tex] = osmotic pressure = 0.285 atm
i = 1
Given mass of protien (solute) = 54.1 mg = 0.0541 g (Conversion factor: 1 g = 1000 mg)
Volume of solution = 1.5 mL
R = Gas constant = 0.0821 L.atm/mol.K
T = temperature = [tex]18^oC=[18+273]=291K[/tex]
Plugging values in equation 1:
[tex]0.285atm=1\times \frac{0.0541\times 1000}{\text{Molar mass of protein}\times 1.5}\times 0.0821L.atm/mol.K\times 291K\\\\\text{Molar mass of protein}=\frac{1\times 0.0541\times 1000\times 0.0821\times 291}{0.285\times 1.5}\\\\\text{Molar mass of protein}=3023.41g/mol[/tex]
Hence, the molar mass of protein A is 3023.41 g/mol.
The molar mass of the protein is 3018 g/mol.
We know that the osmotic pressure is obtained using the formula;
Osmotic pressure = iMRT
i = Van't Hoff factorM = molar concentrationR = gas constantT = absolute temperatureconcentration of the protein = 54.1 * 10^-3g/M/ 1.5 * 10^-3 L
Where M = molar mass of the protein
So;
0.285 atm = 54.1 * 10^-3g/ 1.5 * 10^-3 L M * 0.0821 L.atm/mol.K * 291 K
0.285 = 1.29/1.5 * 10^-3M
M = 1.29/0.285 * 1.5 * 10^-3
M = 3018 g/mol
Learn more about osmotic pressure: https://brainly.com/question/4631715
Academic Vocabulary The schools in one area are
often called a school system. What are some of the
components of this system?
Explanation:
Standards.
Assessments.
Accountability.
Professional Development.
School Autonomy.
Parent Involvement.
Learning Readiness.
Technology.
Please help
Calculate the sodium ion (Na+) concentration for a 0.812 M Na3PO4 solution.
[Na+]=____M
Explanation:
Correct option is
B
0.750 M
Na3PO4 dissociates as:
Na3PO4⇌3Na++PO43−
∴ conc. of Na+ would be =3×0.250=
hope help
How many grams of gasoline would you need to burn to move your car 2.5 miles which takes 5,375 kJ? (Hrxn= 47kJ/g)
Answer:
1.1 × 10² g
Explanation:
The combustion of gasoline releases energy that is used to move the car. The enthalpy of reaction (ΔH°rxn) of the combustion of gasoline is 47 kJ/g, that is, 47 kiloJoule are produced per gram of gasoline burned. The mass of gasoline to be burned to release 5,375 kJ is:
5,375 kJ × 1 g Gasoline/47 kJ = 1.1 × 10² g
3. If a gas exerts 1.2 atm of pressure at a volume of 31 liters and a temperature of 360K, how many moles of the gas are in the container.
how many grams of zinc sulfide are used to produce 1.28 grams of zinc oxide?
Answer:
0.012288122055459
Explanation:
i might be wrong
What is the concentration of a solution that has a volume of 2.5 L and contains 660 g of calcium phosphate? (molar mass of calcium phosphate = 310.18 g/mol)
Answer:
0.85 M
Explanation:
Step 1: Given data
Mass of calcium phosphate (m): 660 gVolume of solution: 2.5 LMolar mass of calcium phosphate (M): 310.18 g/molStep 2: Calculate the moles (n) corresponding to 660 g of calcium phosphate (solute)
We will use the following expression.
n = m/M
n = 660 g/(310.18 g/mol) = 2.13 mol
Step 3: Calculate the molar concentration (molarity) of the solution
Molarity is equal to the moles of solute divided by the liters of solution.
M = 2.13 mol/2.5 L = 0.85 M
How much aluminum oxide in grams is produced from the reaction of 3.5 moles of oxygen with 4.5 moles of aluminum?
Answer:
The mass of 3.5 moles of Ca is 140 g to two significant figures
At 1115 degrees Celcius, where iron is still a solid (melting point 1538 degrees Celcius), the unit cell for the most stable crystal lattice of the metal is face- centered cubic (fcc) with an edge length of 362 pm. What is the atomic radius of iron at this temperature?
Answer: The atomic radius of iron is 128 pm.
Explanation:
To calculate the radius of the metal having FCC crystal lattice, the relationship between edge length and radius follows:
[tex]4r=\sqrt{2}a[/tex]
Where,
a = edge length = 362 pm
r = atomic radius of iron = ?
Plugging values in above equation, we get:
[tex]r=\frac{\sqrt{2}\times 362}{4}\\\\a=128pm[/tex]
Hence, the atomic radius of iron is 128 pm.
Please help me I need help with this questions I’m very confused fused as to what the answer is please
Suppose you have 250g of gold(I) Chloride. How many grams of Gold do you have?
29.26 gram
Explanation:
No of molecules = no of mole × Avogadro's number
No of molecules = mass in gram/ molar mass × Avogadros number
Mass in gram =No of molecules×molar mass / Avogadros number
Mass in gram = 3.012 ×10^23 × 58.5/6.02×10^23
29.26 gram
Write the empirical formula of at least four binary ionic compounds that could be formed from the following ions: Ca^2 , Al^3 ,I^-,S^2-
Answer:
Write the empirical formula of at least four binary ionic compounds that could be formed from the following ions: Ca^2 , Al^3 ,I^-,S^2-
Explanation:
1)Formula of calcium iodide:
The compound of Ca^2+ and I^-1:
[tex]CaI_2[/tex]
2) Formula of calcium sulfide:
[tex]CaS[/tex]
3) Formula of aluminum iodide:
[tex]AlI_3[/tex]
4) Formul aluminum sulfide:
[tex]Al_2S_3[/tex]
These are the four ionic compounds that are formed.
Which of the following IS TRUE for covalent bonding?
A. Covalent bonding involves the sharing of electrons
B. Covalent bonding occurs between metals
C. Covalent bonding occurs between non-metals
D. Covalent bonding occurs between atoms with a large electronegativity
difference.
E. Both A and D
F. Both A and C
G. Both C and D