she will have to listen to all of carefully while she is writing for example:
she will listen and look at her writing page (where she writes) she looks while she listens and writes what she hears for example again:
(pretend as i am her.)
"Hey mom, dad, brother come i see crabs!" as she writes it she focuses on how she writes and stops the video and back up again to listen so she can see if it was correct.
Which of the following is best described by the term macroscopic?
A. Water in the liquid phase boils to become a gas.
B. Water molecules in the solid phase are tightly held together.
C.H2O
D. Water is composed of two hydrogen atoms and one oxygen atom.
Answer:
A
Explanation:
Since macroscopic means visible to the naked eye without a microscope it would be A. This is because we can see active phase changes in real time without any magnification like water boiling or ice melting.
Answer:
a is the correct answer
Explanation:
WILL GIVE BRAINLiest
!!!! What is the electron configuration of the gallium ion? -1 s 22 s 22 p 63 s 23 p 6 -1 s 22 s 22 p 63 s 23 p 54 s 1 -1 s 22 s 22 p 63 s 23 p 63 d 10 -1 s 22 s 22 p 63 s 23 p 64 s 24 p 6
Answer:
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p1
Explanation:
By far, the most common ion of group 13 metals are 3+ .
So the common gallium ion is Ga³+ and it's electron configuration is [Ar] 3d10.
Hope it helps.
We can see here that the correct electron configuration of the gallium ion (Ga^3+) is: 1s^2 2s^2 2p^6 3s^2 3p^6
What is electron configuration?Electron configuration refers to the distribution of electrons in the electron shells and subshells of an atom. It is a fundamental concept in atomic structure and describes how electrons occupy specific energy levels around the nucleus of an atom.
When gallium loses three electrons to form a +3 ion (Ga^3+), it becomes a cation. The electron configuration of a neutral gallium atom is 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^1.
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What precipitate sometimes forms during an acid-base neutralization reaction?
a)
sugar
b) water
c) salt
d) carbon
Answer:
The answer is option C.
Salt
Hope this helps you
I really need help!!!
look at the three chemical equations below. How many atoms of each element are in reactants? How many atoms of each element are in the products?
2H2 + O2➔ 2H2O
2Fe203➔ 4Fe+ 3O2
CI2+ 2NaBr➔ 2NaCI+ Br2
Find the 5 number summary for the number of chapters in the Old Testament. (Recall that the 5-number summary is the minimum, lower quartile, median, upper quartile, and maximum.)
Hey, I am doing this project right now too. Did you end up figuring out the answer to this? I do not understand this at all. Message me back pls!
Pretend that unbinilium has an atomic mass of 299.01 amu. It is a group 2A element.
In the future, a local scientist reports that they have successfully synthesized 0.0295 moles of unbinilium. How many grams of unbinilium is this?
Do not enter units.
Answer:
8.82g
Explanation:
In this lab procedure, the ___ variable is the number of half-life cycles (time) and the ___ variable is the number (or fraction) of (radioactive) Lincolnium nuclei remaining at that time.
Answer:
Independent, Dependent
Explanation:
In the given lab procedure, the number of half-life cycles or the time in which the number of nuclei in radio-active substance turns into its half would be characterized as the 'independent' variable as it directly affects the dependent variable i.e. 'the number(or fraction) of Lincolnium nuclei remaining at that time.' The number of nuclei would be the dependent variable as it bears the change or effect of a change in the independent variable(half-life cycle).
Answer:
Its independent and dependent
Explanation:
On Edge 2021
How is alchemy different from modern chemistry?
O A. Alchemy experiments only with living things, and chemistry uses
chemicals
O B. Alchemy was practiced before Aristotle, and chemistry has been
popular since his death.
C. Alchemy is not scientific, but chemistry is based on evidence.
O D. Alchemy covers all areas of science, but chemistry covers only
matter.
Answer:
C. Alchemy is not scientific, but chemistry is based on evidence.
Explanation:
Alchemy was based on mystical beliefs instead of the scientific method.
Chemistry is the study of matter and change based on evidence.
A 3.0 mole sample of KCIO3 was decomposed according to the equation:
2KCIO3(s) ===> 2KCI(s) + 3O2(g)
How many moles of oxygen (O2) will be formed?
o 2.5 moles
4.0 moles
3.0 moles
2.0 moles
4.5 moles
Answer:
4.5 moles
Explanation:
From the equation, the mole ratio of KClO3: O2 = 2: 3
Which means, every 2 moles of KClO3 forms 3 moles of O2.
Let the no. of moles of O2 formed be y.
[tex]\frac{2}{3} = \frac{3.0}{y}[/tex]
2y = 3x3
2y = 9
y = 4.5 moles
A ball that has a mechanical energy of 65J has 12J of kinetic energy the ball has ....... of potential energy
Answer:
53J
Explanation:
Total Energy is the sum of Kinetic energy and potential energy.
Which is the main type of element found in the upper right part of the periodic
table?
O A. Metalloids
O B. Nonmetals
O C. Representative metals
O D. Metals
Given the following thermochemical data C(s) + ½O2(g) ---> CO(g) ∆H1 = -111 kJ/mol C(s) + O2(g) ---> CO2(g) ∆H2 = -395 kJ/mol What is the ∆Hr for the reaction: CO(g) + ½O2(g) ---> CO2(g) ∆Hr = ?
Answer:
The enthalpy of the reaction asked is -284 kJ/mol.
Explanation:
Given:
[tex]C(s) + \frac{1}{2}O_2(g)\rightarrow CO(g), \Delta H_1 = -111 kJ/mol [/tex]..[1]
[tex]C(s) + O_2(g)\rightarrow CO_2(g) \Delta H_2 = -395 kJ/mol[/tex]...[2]
To find ; [tex]\Delta H_{rxn}[/tex] of following reaction :
[tex]CO(g) + \frac{1}{2}O_2(g)\rightarrow CO_2(g), \Delta H_{rxn} =?[/tex]..[3]
Using Hess's Law:
[2] - [1] = [3]
[tex]\Delta H_{rxn}=\Delta H_2-\Delta H_1=-395 kJ/mol-(-111 kJ/mol)=-284 kJ/mol[/tex]
The enthalpy of the reaction asked is -284 kJ/mol.
How many molecules would there be in 10.5 L of carbon dioxide at 40.0 C and 252 kPa
Answer:
6.14×10²³ molecules
Explanation:
Data obtained from the question include:
Volume (V) = 10.5L
Temperature (T) = 40°C
Pressure (P) = 252 kPa
Next, we shall determine the number of mole of CO2 present.
This can be obtained by using the ideal gas equation:
PV = nRT
Volume (V) = 10.5L
Temperature (T) = 40°C = 40°C + 273 = 313K
Pressure (P) = 252 kPa
Gas constant (R) = 8.31 KPa.L/Kmol
Number of mole (n) =.?
PV = nRT
252 x 10.5 = n x 8.31 x 313
Divide both side by 8.31 x 313
n = (252 x 10.5) /(8.31 x 313)
n = 1.02 mole
Therefore, 1.02 mol of CO2 is present.
Now, we can obtain the number of molecules of CO2 present as follow:
From Avogadro's hypothesis, 1 mole of any substance contains 6.02×10²³ molecules.
This means that 1 mole of CO2 also contains 6.02×10²³ molecules.
Now, if 1 mole of CO2 contains 6.02×10²³ molecules,
Then 1.02 mole will contain = 1.02 x 6.02×10²³ = 6.14×10²³ molecules.
Therefore, 6.14×10²³ molecules of CO2 is present.
Mass box A = 10 grams; Mass box B = 5 grams; Mass box C-made of one A and one B
How many boxes of B would be required to make 30 grams of C?
hy
Answer:
2 boxes
Explanation:
==>Given that:
Box A = 10 grams
Box B = 5 grams
Box C= 1 A and 1 B = 15 grams
==>Required:
Number of boxes of B that would make 30 grams of C
==>Solution:
We know that, 1 box of B would give us 15grams of of C when mixed in the right proportion with 1 box of A.
thus,
1 box of B => 15 grams of C
x box of B => 30 grams of C
Therefore x = (30*1)/15
x = 30/15
x = 2
2 boxes of B would be required to make 30 grams of C
MODomy
OCTORS
Question 14 Multiple Choice Worth 5 points)
(07.04 MC)
The final stage of polymerase chain reaction to create a new strand of DNA that binds to the original strand, where special enzymes
attach to primers and attach complementary bases along the strand, is called
annealing
extension
denaturing
hybridization
Question 15/Multiple Choice Worth 5 points)
7
(07.04 MC)
Answer:
hybridization is the correct answer i guess
Answer:
Extension
Explanation:
PCR has three stages: denaturing, annealing, and extension (in this order).
I, myself, took this exam and got the answer correct.
What is the concentration of a solution when 50.0 mL of 0.436 M NH ₄NO ₃ is diluted to a new volume of 250.0 mL
Answer:
0.0872 M
Explanation:
Use the equation M1V1 = M2V2
0.436(50.0) = (x)(250.0)
21.8 = 250x
0.0872 = x
In the equation 2KCIO3 → 2KCI + 302, how many moles of oxygen are produced when 12.61 mol of
KCIO3 decompose completely?
Select one:
O a. 19
Ob. 8.4
O c. 6.3
O d. 13
PLEASE I AM BEGGING PLEASE HELP ME
Answer:
A 19
Explanation:
2 mole of KClO3 produces 3 mole of O3
2 : 3
1 : 3/2
12.61 : 3/2 × 12.61
12.61 : 18.9
12.61 mole of KClO3 produces 18.9mole of O2.
Based on the graph, describe what is happening between 4 and 6 seconds. The object is moving away from the start at a constant speed. The object is not moving. The object is returning to the start at a constant speed. The object is changing speed.
Answer:
The object is not moving.
Explanation:
Since the position doesn't change during 4-6 (remains constant at 12m) it tells us that object is not moving and remaining at constant distance from start point.
Answer:
The object is not moving.
Explanation:
Since the distance hasn't changed from 4 seconds to 6 seconds, we know that the distance from the start stays the same between the time period. The object isn't moving away or moving closer at a constant speed, but is staying the same, constant distance away at a constant speed. Therefore, the object isn't moving.
In the past mining companies were not made responsible for the clean-up of any of
the mine sites. As a result, abandoned mines had a severe impact on the
environment in Ontario. Which of these is not a result of these mining practices?
a)
Chemical reactions producing sulphuric acid decrease soil and water ph in the
area.
b)
Acid leaching dissolves metals found in the soil thus allowing them to enter
the water system.
c)
Heavy metals which are left tailing ponds can dissolve and enter the water
system.
d)
Old and inefficient mining smokestacks contaminate the soils around
abandoned mine sites.
In order from left to right, what are the coefficients (front numbers) needed to
balance the following equation? CzH6 + O2- CO2 + H20*
Answer:
10CH6 + 10O2 → 10CO2 + 3H20
Explanation:
Consider the combustion of octane:
2C8H18(g) + 2502(g) ===> 16CO2(g) + 18H2O(g)
Calculate the mass of water (H20) produced from 11.2 grams of octane (C3H18) assuming excess
oxygen.
15.9 g
O 0.196 g
O 4.31 g
1.77g
14.1g
Answer:
15.9 g
Explanation:
(Take the atomic mass of C=12.0, H=1.0, O=16.0)
no. of moles = mass / molar mass
no. of moles of octane used = 11.2 / (12.0x8 + 1x18)
= 0.0982456 mol
Since oxygen is in excess and octane is the limiting reagent, the no. of moles of H2O depends on the no. of moles of octane used.
From the balanced equation, the mole ratio of octane : water = 2:18 = 1: 9,
so this means, one mole of octane produced 9 moles of water.
Using this ratio, we can deduce that (y is the no. of moles of water produced):
[tex]\frac{1}{9} =\frac{0.0982456}{y}[/tex]
y = 0.0982456x9
y= 0.88421 mol
Since mass = no. of moles x molar mass,
mass of water produced = 0.88421 x (1.0x2+16.0)
=15.9 g
How many Liters of 18 M H2SO4 are needed to make 0.5 L of 1.5 M H2SO4
Answer:
0.04 L
Explanation:
The following data were obtained from the question:
Concentration of stock solution (C1) = 18M
Volume of stock solution needed (V1) =?
Concentration of diluted solution (C2) = 1.5M
Volume of diluted solution (V2) = 0.5L
The volume of the stock solution needed can be obtain by using the dilution formula.
This is illustrated below:
C1V1 = C2V2
18 x V1 = 1.5 x 0.5
Divide both side by 18
V1 = (1.5 x 0.5)/18
V1 = 0.04L
Therefore, the volume of the stock solution needed is 0.04L.
The pH of a substance can only be determined when it is
a) dried in a powder
b) frozen
c) dissolved in water
d) heated
The pH of a substance can only be determined when it is frozen. Hence, option B is correct.
What is pH?pH stands for Hydrogen potentials.
The use of the pH scale is one practical way of quantitatively determining how acidic something is.
If the pH of a solution is less than 7, it is acidic. If the pH is 7, the solution is neutral and if the pH is greater than 7,the solution is basic.
The pH of a substance can only be determined when it is frozen. Hence, option B is correct.
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Calculate the volume in liters of a 0.00183g / L mercury(1) chloride solution that contains 125 mg of (Hg 2 Cl 2 ) .
Answer: 68.3L
Explanation:
Density = Mass / Volume
Density = 0.00183 g/L
Mass = 125 mg = 0.125g
Volume = Mass / Density = 68.3L
When dissolved in water, an acid or a base breaks down into a proton and an electron. two negative ions. a positive and a negative ion. a positive ion and a proton.
Answer:
got c
Explanation:
When dissolved in water, an acid or a base breaks down into a positive and a negative ion.
What is an acid-base reactions?
An acid–base reaction is a chemical reaction that occurs between an acid and a base. Acid-base reactions can be used to determine pH.
When dissolved in water, acids donate hydrogen ions (H+). Hydrogen ions are hydrogen atoms that have lost an electron and now have just a proton, giving them a positive electrical charge, whereas, bases, when dissolved in water yield hydroxide ions (OH-).
If a solution has a high concentration of H+ ions, then it is acidic whereas the solution having high concentration of OH- ions, called as basic.
Thus, from above , it is clear that when dissolved in water, an acid or a base breaks down into a positive and a negative ion.
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plz help!!!!!!
This equation for the reaction when solid magnesium and solid lead (II) oxide are heated together is:
Mg(s)+Pb(s) => MgO(s)+Pb(s)
a)what does tell you about the position of lead in the reactivity series? explain your answer.
b)rewrite equation as an ionic equation
this shows that magnesium is higher in the reactivity series than lead.
I don't think there can be an ionic equation written because both components are in solid form and neither is in an aqeuos state.
Reactivity series is the progression of the metals based on the activity. In a reaction between magnesium and lead (II) oxide, it can be said that lead is at a lower position in the reactivity series.
What is reactivity series?Reactivity series is the depiction of the metals in a decreasing order based on their ability to displace the other metal in the reaction. More reactive species are placed at the upper position, while the less reactive species are placed at the lower positions.
In the series, magnesium is placed at the upper part of the series and has high reactivity, whereas lead is placed at the lower level with low reactivity. hence, in the reaction, Mg replaces Pb and forms a bond with oxygen.
The reaction between magnesium and lead (II) oxide cannot be written in the ionic form as all the reactants and the products are in the solid state and not in an aqueous state.
Therefore, lead is at a lower level of reactivity series.
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250 g H 2 SO 4 completely reacted with aluminum?
2AI(s) + 32504(aq)- AI2 (504) 3(aq) + 3H 2 (9)
0.85g
450g
290g
870g
Answer: 290 g of aluminium sulphate is produced.
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} H_2SO_4=\frac{250g}{98g/mol}=2.55moles[/tex]
The balanced chemical reaction is:
[tex]2Al(s)+3H_2SO_4(aq)\rightarrow Al_2(SO_4)_3(aq)+3H_2(g)[/tex]
According to stoichiometry :
3 moles of [tex]H_2SO_4[/tex] produce = 1 mole of [tex]Al_2(SO_4)_3[/tex]
Thus 2.55 moles of [tex]H_2SO_4[/tex] will require=[tex]\frac{1}{3}\times 2.55=0.85moles[/tex] of [tex]Al_2(SO_4)_3[/tex]
Mass of [tex]Al_2(SO_4)_3=moles\times {\text {Molar mass}}=0.85moles\times 342g/mol=290g[/tex]
Thus 290 g of aluminium sulphate is produced.
SERE
What type of energy is the sum of an object's potential and kinetic energy?
mechanical energy
electromagnetic energy
chemical energy
thermal enemy
Answer:
Mechanical energy
Answer:
Mechanical Energy
Explanation:
The mechanical energy is the sum of the objects potential energy (energy the object possess due to its position) and its kinetic energy (energy the object possess due to its motion). Adding this two energies together, gives the total mechanical energy.
Determine the [H+] or [OH−] for each of a solutions at 25°C.
Solution B: [H3O+] = 9.99 x 10^-9 M
Solution B: [OH-] = ?
Solution C: [H3O+] = 0.000777 M
Solution C: [OH-] = ?
Answer:
Solution B: [OH-] = 1×10^–6 M
Solution C: [OH-] = 1×10^–6 M
Explanation:
Solution B:
Hydronium ion concentration, [H3O+] = 9.99×10^–9 M
Hydroxide ion concentration, [OH-] = ?
The Hydroxide ion concentration, [OH-] can be obtained as follow:
[H3O+] × [OH-] = 1×10^–14
9.99×10^–9 × [OH-] = 1×10^–14
Divide both side by 9.99×10^–9
[OH-] = 1×10^–14 / 9.99×10^–9
[OH-] = 1×10^–6 M
Therefore, the Hydroxide ion concentration, [OH-] is 1×10^–6 M
Solution C:
Hydronium ion concentration, [H3O+] = 0.000777 M
Hydroxide ion concentration, [OH-] = ?
The Hydroxide ion concentration, [OH-] can be obtained as follow:
[H3O+] × [OH-] = 1×10^–14
0.000777 × [OH-] = 1×10^–14
Divide both side by 0.000777
[OH-] = 1×10^–14 / 0.000777
[OH-] = 1.29×10^–11 M
Therefore, the Hydroxide ion concentration, [OH-] is 1.29×10^–11 M
Which of the following elements will not form a polar covalent bond with oxygen?
A. Hydrogen
B. Sodium
C. Oxygen
D. Fluorine
sodium will form an ionic bond
Answer:
C. Oxygen
Explanation:
Oxygen will not form a polar covalent bond with another oxygen atom because when 2 atoms of the same element bond, it is a nonpolar covalent bond.
Since they are the same element, the 2 oxygens have the same electronegativity and will share their electrons equally.
Polar covalent bonds involve 2 atoms that will share electrons unequally