Answer:
A. zinc metal
Explanation:
Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a blue-silvery appearance when oxidation is removed. It is the first element in group 12 of the periodic table.
Answer:
A.) Zinc (Zn) is a metal
Explanation:
Hope this helps!
why are state symbols used in chemical equations
Answer:
state symbol meaning
[s] solid
liquid
gas
aq] aqueous dissolved in water
Explanation:
often chemical equations are written showing the state that each substance is in. the [s] sign means that the compound is a sold. the l sign means the substance is a liquid. the aq sign stands for aqueous in water and means the compound is dissolved in water
thank me later.
A chemical reaction is a process in which what
Products produced reactants
The law of conservation of mass applies
Combustion always occurs
None of the above
the law of conservation of mass applies.....?
which of the following is an example of an empirical formula?
A. C4H10
B. C2H6
C. CO2
D. H2O2
how many moles are in 3.00x 10^22 atoms of He?
Answer:
0.05 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{3.0 \times {10}^{22} }{6.02 \times {10}^{23} } \\ = 0.049833...[/tex]
We have the final answer as
0.05 molesHope this helps you
Pls help me plsssss my mom is coming home soon I’ll mark brainliest hurrrrrrrrry
Answer:
Its A, sorry I wrote something else.
Explanation:
The equator is the warmest, and the sunlight is not pointing towards point A.\
Friendly guy that likes to help
Only 2.5% of Hydrosphere are freshwater, if only 31% of it are groundwater which we can drink right away, how many percent of our hydrosphere can be used as drinking water?
a. 0.78%
b. 1.73%
c. 12.4%
d. 28.5%
Answer:
a. 0.78%
Explanation:
Given data:
Total percentage of hydrosphere = 2.5%
Percentage of ground water = 31%
Percentage of hydrosphere we use for drinking = ?
Solution:
Percentage of hydrosphere we use for drinking = Percentage of ground water /100 × Total percentage of hydrosphere
By putting values,
Percentage of hydrosphere we use for drinking = 31 / 100× 2.5
Percentage of hydrosphere we use for drinking = 0.78%
Calculate the percentage by mass of oxygen in Al2(SO4)3 (Al=27, S=32,O= 16) PLEASE SHOW FULL WORKING
Answer:
There is 61.538% oxygen in Al2(SO4)3.
Explanation:
Wt Of oxygen in the compound = 12*16 = 192 amu.
Total Wt. Of the compound = 2*12+3*32+12*16 = 312 amu.
Thus, percent of oxygen = Wt of oxygen/total Wt. Of compound *100
= 192/312 * 100=61.538 %
Will be giving brainliest for correct answer.
2KI+Pb(NO3)2
Create a balanced equation for the Lead (II) nitrate and potassium iodide solution.
What's the reaction type?
I believe its a double replacement and redox reaction. Correct me if I'm wrong.
I will be reporting random answers
Answer:
The balanced chemical equation is Pb(NO3)2 + 2KI produces PbI2 + 2K(NO)3. In chemistry, this is called a double replacement reaction. Lead nitrate and potassium iodide, which are the reactants, are powders that react to form a yellow-colored lead iodide and a colorless potassium nitrate.
Explanation:
Answer:
2KI+Pb(NO3)2 ⇒ PbI2 + 2KNO3
Who discovered electrons using Crookes tubes?
a.) Democritus
b.) Ernest Rutherford
c.) Hantaro Nagaoka
d.) J. J. Thomson
e.) John Dalton
f.) Niels Bohr
Answer:
D. j.j thomson is the correct answer
Explanation:
just answered a similar question
How many molecules are in 7.50 mol of SO2
Answer:
45.165 × 10²³ molecules
Explanation:
Given data:
Number of moles of SO₂ = 7.50 mol
Number of molecules = ?
Solution:
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ molecules
7.50 mol × 6.022 × 10²³ molecules
45.165 × 10²³ molecules
How many more valence electrons does chlorine need to satisfy the octet rule? Chlorine is in group 17
Answer:
1
Explanation:
Octet meaning 8. So if chlorine already has 7 valence electrons it will only need to get 1 more to be satisfied.
Iodine is 80% 127I, 17% 126I, and 3% 128I. Calculate the average atomic mass of Iodine.
Given
80% 127I, 17% 126I, and 3% 128I.
Required
The average atomic mass
Solution
The elements in nature have several types of isotopes
Atomic mass is the average atomic mass of all its isotopes
Mass atom X = mass isotope 1 . % + mass isotope 2.% + ... mass isotope n.%
Atomic mass of Iodine = 0.8 x 127 + 0.17 x 126 + 0.03 x 128
Atomic mass of Iodine = 101.6 + 21.42 + 3.84
Atomic mass of Iodine = 126.86 amu
balance:
Fe2(SO4)3 +
_K[OH] —> _K2[SO4] +
K[SO] + Fe[OH]3
Balance the reaction of Fe2(SO4)3 + KOH = K2SO4 + Fe(OH)3 using this chemical equation balancer! ... Fe2(SO4)3 + 6KOH → 3K2SO4 + 2Fe(OH)3 ...
Missing: _K[ | Must include: _K[
Answer:
Fe2(SO4)3 + 6 KOH → 2 Fe(OH)3 + 3K2SO4
Explanation:
What is an explanation of a natural phenomenon supported by large amounts of data called?
Select one:
a.scientific law
b.theory
c.conclusion
d.hypothesis
Answer:
scientific law is the answer of these questions
Which evidence shows that heat is given off when a candle burns?
A. A match is used to light the candle.
B. The burning candle produces a yellow flame.
O c. Covering the burning candle extinguishes the flame.
D. Solid candle wax near the flame melts as the candle burns.
thing
Answer:
D. solid candle wax near the flame melts as the candle burns.
Answer:
Part D, melting is a product of heating
Explanation:
If Veronica spins in a circle with the compass in her hand, which force keeps the compass' needle pointing north?
A.
an electrical force
B.
a magnetic force
C.
a contact force
D.
a gravitational force
If Veronica spins in a circle with the compass in her hand, then the force which keeps the compass' needle pointing north is magnetic field.
What is magnetic force?The magnetic influence on moving electric charges, electric currents, and magnetic materials is described by a magnetic field, which is a vector field. In a magnetic field, a moving charge receives a force that is perpendicular to both its velocity and the magnetic field.
The magnetic field is defined as a region where the force is active along imaginary lines. This force has an effect on all magnetized objects from the south magnetic pole to the north magnetic pole, including the needle of a compass. The needle always points north magnetic pole under the influence of the Geomagnetic field.Hence the required force is a magnetic force.
To know more about magnetic forces, visit the below link:
https://brainly.com/question/14411049
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What is one property of salts?
Answer:
They are neutral
Explanation:
Salts are chemical compounds formed when acids and a bases are combined together. Both substances nuetralize each other as they react, thereby forming salts which are neutral substances. This resultant compounds are neither basic nor acidic. They have a pH of 7, which makes them neutral in nature.
How much heat is required to change 48.5 liquid mercury (Hg) at 400 K to vapor at a 700 K? The boiling point of mercury is 629.88 K
-88 kj
-204 kj
16.2 kj
30 kj
29 kj
Answer: 4.91 kJ
Explanation:
The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.
[tex]Q=m\times c_l\times (T_(f,l)-T_(i,l))+m\imes L+m\times c_v\times T_(f,v)-T_(i,v)[/tex]
Q = Heat absorbed = ?
m= mass of mercury = 48.5 g = 0.0485 kg
c = specific heat capacity = [tex]0.14kJ/kgK[/tex]
L = heat of vaporization = 59.2 kJ
Initial temperature of liquid mercury = [tex]T_i[/tex] = 400 K
Final temperature of mercury vapor = [tex]T_f[/tex] = 700 K
Putting in the values, we get:
[tex]Q=0.0485\times 0.14\times (629.88-400)+0.0485\times 59.2+0.0485\times 0.14\times (700-629.88)[/tex]
[tex]Q=1.56+2.87+0.476[/tex]
[tex]Q=4.91kJ[/tex]
Answer:
16.2 kj
Explanation:
1.56kj + 14.31kj + 0.34kj
If the caterpillar keeps moving at the same speed, how long will it take to travel 6cm?
It will take 15 s to travel 6 cm
Further explanationGiven
distance versus time graph
Required
time travel
Solution
Caterpillar motion is a straight motion with a constant speed, so that the graph between distance and time forms a diagonal line
If we look at the graph, we can determine the time taken when the distance reaches 6 cm (y axis) by drawing a line to the diagonal line and cutting the x-axis as time, and we get 15 s
Or we can also use the formula for motion at constant speed:
d = v x t
With v at point 2,5 of 2/5 m / s, so the time taken:
[tex]\tt t=\dfrac{d}{v}=\dfrac{6}{2/5}=15~s[/tex]
Balance this chemical equation
Answer:
3
Explanation:
On the left side we have 3 Calcium atoms and 6 fluorine atoms
that means there need to be the same number on the right side
in the CaF2 molecules we already have 2 fluorine atoms so by multiplying with 3 we get 3 Ca and 6F
110 A common liquid contains 11.19% hydrogen
and 88.81% oxygen by mass.
a) Calculate the number of moles of hydro-
gen atoms and oxygen atoms in 100.0 g of
this liquid.
Explanation:
number of moles =[tex] \frac{given \: mass}{molar \: mass} [/tex]
thus, number of moles of hydrogen= 11.91/1=> 11.91number of moles of oxygen= 88.81/32 = 2.77=> 2.77hope it helps:)
The tube that stores sperm cells
Answer:
here is the answer
Explanation:
The epididymis
Answer:
Vas deferens.
Explanation:
A long tube that is located near each testicle. The epididymis is the tube which moves the sperm from the testicles. Vas deferens. This is a tube in which the sperm is stored and it carries the sperm out of the scrotal sac.
1. How many moles of NaCl would be contained in .750 L solution with a molarity of
0.45M?
Answer:
[tex]\boxed {\boxed {\sf 0.3375 \ mol \ NaCl}}[/tex]
Explanation:
Molarity is found by dividing the moles of solute by liters of solution.
[tex]M=\frac{moles \ of \ solute }{liters \ of \ solution}[/tex]
We know the molarity is 0.45 M and there are 0.750 liters of solution. The solute is NaCl (sodium chloride). We can substitute the values into the formula.
[tex]0.45 \ M = \frac{ moles \ of \ NaCl}{ 0.750 \ L }[/tex]
The molarity (M) can also be represented by mol/L
[tex]0.45 \ mol/L = \frac{ moles \ of \ NaCl}{ 0.750 \ L }[/tex]
We are solving for the moles of solute, so we must isolate the numerator. It is being divided by 0.750 liters. The inverse operation is multiplication, so multiply both sides of the equation by 0.750 L.
[tex]0.750 \ L * 0.45 \ mol/L = \frac{ moles \ of \ NaCl}{ 0.750 \ L }*0.750 \ L[/tex]
The liters will cancel out.
[tex]0.750 * 0.45 \ mol = { moles \ of \ NaCl}[/tex]
[tex]0.3375 \ mol \ = moles \ of NaCl[/tex]
There are 0.3375 moles of NaCl in a 0.750 liter solution with a molarity of 0.45 M.
Which type of galaxy forms when two other galaxies crash into each other? They are small galaxies made up of bright, young stars.
Answer:
elliptical galaxy
Explanation
:The combination of the two galaxies then forms what appears to be an elliptical galaxy as the arms begin to disappear. The merger of gasses creates new stars, and the new shape becomes more elliptical, globular, or sometimes irregular.
Ude was asked by his teacher to draw an angle that measures 130 degrees. He isn't even sure where to start. Explain to Jude how you would use a protractor to draw this angle.
Answer:
Explanation:
To construct an angle of 130 degrees;
The first thing to do is to bisect a given line segment.
Let's say we measure an even straight line A to B. Line A to B is assumed to be 10 cm. Then, we will choose any convenient radius and draw an arc at A and B.
Then, we proceed by draw arcs to cut each other at P and Q. Join |PQ| to cut |AB| at R. R is the midpoint of |AB|.
After, we bisect a given line segment where point R which is half of line AB.
Using the R to B side;
Then, we place our protractor at R; Starting from zero degrees with the horizontal line (parallel to side B) . we mark out angle 130° after we have counted all the way from 0° to 130°. At 130°, we mark out the point (X) on the paper and draw the extended line till it joins at R.
The angle from B to X is angle 130°
Unsaturated compounds _____.
do not readily react
have a high activation energy
require UV light to react
are very reactive
Answer:
are very reactive
Explanation:
1. Matter is anything that has and takes up mass and occupies space why is it saying it's wrong Pls help
Answer:
Matter is anything that has mass and takes up space.I think there is takes up already synonym to occupies.
What is the kinetic energy of a 5 kg object moving at 7 m/s?
Answer:
122.5 Joule, or 122.5 j
Explanation:
Given,
mass of the object (m) = 5 kg
velocity of the object (v) = 7 m/s
Kinetic energy = [tex]\frac{1}{2}[/tex] × m × v²
Applying the formula:
Kinetic energy = [tex]\frac{1}{2}[/tex] × 5 × 7²
⇒ [tex]\frac{1}{2}[/tex] × 5 × 7 × 7
⇒ [tex]\frac{245}{2}[/tex]
⇒ 122.5 Joule, or 122.5 j
Kinetic energy is the energy that an object gains as the result of the motion. It also depends on the mass of the object and force with which the motion is applied. In the given question, the mass of the object is 5 kg and the force of the velocity by which it is moving is 7 m/s.
Sulphur and Magnesium are separately burnt in air. Name the products formed. When these products are dissolved in water and the solutions obtained are tested with litmus, what will be the result? Why?
Answer: Magnesium turns red litmus blue and sulphur turns blue litmus red.
Explanation:
When a metal reacts with oxygen present in air, it forms basic oxide which simply means when they react with water, they form basic solution.
The chemical equation for the burning of magnesium (metal) in air and reaction with water of the product so formed are as follows:
[tex]2Mg+O_2\rightarrow 2MgO[/tex]
[tex]MgO+H_2O\rightarrow Mg(OH)_2\text{ (base)}[/tex]
When a non- metal reacts with oxygen present in air, it forms acidic oxide which simply means when they react with water, they form acidic solution.
The chemical equation for the burning of sulphur (non-metal) in air and reaction with water of the product so formed are as follows:
[tex]S+O_2\rightarrow SO_2[/tex]
[tex]SO_2+H_2O\rightarrow H_2SO_3\text{ (acid)}[/tex]
There are 2 types of litmus:
Red litmus: They turn the solution blue when dipped in basic solution.Blue litmus: They turn the solution red when dipped in acidic solution.Therefore, here, magnesium forms a basic solution, therefore it will turn red litmus blue whereas sulphur forms an acidic solution, so it will turn blue litmus red.
Does this model demonstrate the conversation of matter?how do you know?
Answer:
No, the model does not demonstrate the conservation of matter
Explanation:
The principle of conservation of matter states that matter can neither be created nor destroyed but is transformed from one form to another.
If we look at the model presented, the products on the right hand side and the reactants on the left hand side, we will notice that there is a loss of matter from left to right.
As a result of this, the model does not show the principle of conservation of matter.