Answer:
There would be [tex]20[/tex] neutrons in that atom.
Explanation:
The mass number of an atom is the sum of:
the number of neutrons in this atom, andthe number of protons in this atom.Electrons do not contribute to the mass number of an atom.
From the question:
Mass number of this atom: [tex]39[/tex].Number of protons in this atom: [tex]19[/tex].[tex](\text{Mass Number}) = (\text{Number of protons}) + (\text{Number of neutrons})[/tex].
In this atom:
[tex]39 = 19 + (\text{Number of neutrons})[/tex].
Hence, the number of neutrons would be [tex]39 - 19 = 20[/tex].
Smoking cigarettes is a lifestyle choice that may lead to cardiovascular disease.
Some people who have never smoked cigarettes still have cardiovascular disease.
Give two other factors that may contribute to the occurrence of cardiovascular
disease.
Answer:
High blood pressure. High blood pressure (hypertension) is one of the most important risk factors for CVD.
High cholesterol - High-fat diet.
What is the value that is MEASURED in a lab?
Answer:
To use standard laboratory measurement devices to measure length, volume and mass amounts.
Why do atoms connect to eachother?
Answer:
electrons can bond atoms together
Explanation:
when two atoms share electrons,they are locked together by that sharing.These are called covalent bonds...but when an atom gives one of its electrons to another atom ,they are held together by electric forces.HOPE THAT HELPED☺
Explanation:
electron can bond each other
A gas at a temperature of 300 K occupies a 5 L flexible container at a pressure of 150 kPa. What volume will it occupy at STP?
6.73 L
This one requires the combined gas law.
P1V1/T1 = P2V2/T2
P1 = 150 kPa = 1.48 atm
V1 = 5 L
T1 = 300 K
P2 = 1 atm
V2 = This is what we’re solving for.
T2 = 273 K
P2 and T2 are based on the conditions of STP. I also changed P1 to atm to keep the units consistent.
Solve the equation for V2:
V2 = P1V1T2 / T1P2
V2 = (1.48 atm)(5 L)(273 K) / (300 K)(1 atm) = 6.73 L
Calcule el volumen de disolución de LiOH a 3.5 M, necesario para neutralizar una disolución de 25 ml de H2SO3 cuya densidad es de 1.03 g/ml y su riqueza del 60%. (60 PTS.) Alguien puede ayudarme con esto porfabor
Respuesta:
0.11 L
Explicación:
Paso 1: Escribir la ecuación balanceada
2 LiOH + H₂SO₃ ⇒ Li₂SO₃ + H₂O
Paso 2: Calcular la masa de solución de H₂SO₃
25 mL de solución de H₂SO₃ tiene una denisdad de 1.03 g/mL.
25 mL × 1.03 g/mL = 28 g
Paso 3: Calcular la masa de H₂SO₃ en 26 g de Solución de H₂SO₃
La riqueza de H₂SO₃ es 60%, es decir, cada 100 g de solución hay 60 g de H₂SO₃.
26 g Sol × 60 g H₂SO₃/100 g Sol = 16 g H₂SO₃
Paso 4: Calcular los moles correspondientes a 16 g de H₂SO₃
La masa molar de H₂SO₃ es 82.07 g/mol.
16 g × 1 mol/82.07 g = 0.19 mol
Paso 5: Calcular los moles de LiOH que reaccionan con 0.19 moles de H₂SO₃
La relación molar de LiOH a H₂SO₃ es 2:1. Los moles de LiOH que reaccionan son 2/1 × 0.19 mol = 0.38 mol.
Paso 6: Calcular el volumen de solución de LiOH
0.38 moles de LiOH están en una solución 3.5 M. El volumen requerido es:
0.38 mol × 1 L/3.5 mol = 0.11 L
1. The electron arrangement ions X and Y2 are 2, 8, and 2, 8, 8 respectively.
Write the electronic arrangement of the elements X and Y. (2 mks)
Write the formula of the compound that would be formed between X and Y.
a
mk)
The given question is incomplete. the complete question is:
The electron arrangement ions [tex]X^{3+}[/tex] and [tex]Y^{2-}[/tex] are 2, 8, and 2, 8, 8 respectively.
Write the electronic arrangement of the elements X and Y.
Write the formula of the compound that would be formed between X and Y.
Answer: 1. The electronic arrangement for X and Y are 2,8, 3 and 2,8,5 respectively.
The formula of the compound formed is [tex]X_2Y_3[/tex]
Explanation:
Electronic configuration is the arangement of electrons in an atom in order of increasing energies.
Cations are formed when electrons are lost by atoms and anions are formed when electrons are gained by atoms.
[tex]X^{3+}:2,8[/tex]
[tex]X:2,8,3[/tex]
[tex]Y^{3-}:2,8,8[/tex]
[tex]Y:2,8,5[/tex]
For formation of a neutral ionic compound, the charges on cation and anion must be balanced.
Here element X is having an oxidation state of +3 called as [tex]X^{3+}[/tex] cation and [tex]Y^{2-}[/tex] is an anion with oxidation state of -2. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral [tex]X_2Y_3[/tex]
PLEASE Answer asap! Compare two periodic families below. You must include at least two facts about each family. You may use any description of properties or periodic trends to help you.
Answer:
The alkali metals/group 1 are recognized as a group and family of elements. These elements are metals. Sodium and potassium are examples of elements in this family. Hydrogen is not considered an alkali metal because the gas does not exhibit the typical properties of the group. The largest family of elements consists of transition metals/group 3-12/group 3a. The center of the periodic table contains the transition metals, plus the two rows below the body of the table (lanthanides and actinides) are special transition metals. Even though both are metals, transition metals have higher melting points; they have higher density; they are less reactive with water; they react and form ions with different charges, but Group 1 metals only form 1+ ions. (Hope the is helpful! You can reword it if you want...)(same answer from the other same question you posted)
1. What are the differences between lonic and covalent bonds?
Answer: Ionic bonds result from transfer of electrons, whereas covalent bonds are formed by sharing. ... Ionic bonds are electrostatic in nature, resulting from that attraction of positive and negative ions that result from the electron transfer process; charge separation between covalently bonded atoms is less extreme.
Explanation:
Answer correctly and dont bother coming to this question if you have the wrong answer.
Answer:
it's b or d I am not 100% sure witch one tho
Answer:
B.
Explanation:
It is B because it says which is an example of A PHYSICAL MODEL. B is a physical model becuase by using tennis balls to represent the plantes (including the sun)
it is a model of a problem!!!
Have a great day!
Hope this helps!
-Lea
7. Which word BEST describes symbiosis?
O A. ecosystem
O B. relationship
O C. living
OD. environment
Answer:
d.
Explanation:
po ata d ako sure sorry
a solution is prepared by dissolving 55g of CaCl2 into 300g of water. if the Kf of water is -1.86 c/m, shat is the freezing point depression of the solution
Answer:
Relation between , molality and temperature is as follows.
T =
It is also known as depression between freezing point where, i is the Van't Hoff factor.
Let us assume that there is 100% dissociation. Hence, the value of i for these given species will be as follows.
i for = 3
i for glucose = 1
i for NaCl = 2
Depression in freezing point will have a negative sign. Therefore, d
depression in freezing point for the given species is as follows.
=
=
=
Therefore, we can conclude that given species are arranged according to their freezing point depression with the least depression first as follows.
Glucose < NaCl <
Explanation:
the volume of 5.00 M KBr needed to have 1.00 mol KBr mL
Answer: molarity = mole solute/ liter of solution.
=> volume= mole/molarity = 1/5 = 0.2 L = 200mL
Explanation:
Scientists have been able to find a full record of Earth's fossil history, thus making the fossil record complete.
True or False?
Answer:
False
Explanation:
Few organisms were not preserved as well as others, and new fossils are found every day
what is the ionic equation for dilute hydrochloric acid and magnesium
Answer:
Mg(s) + 2H⁺(aq) ⟶ Mg²⁺(aq) + H₂(g)
Explanation:
A net ionic equation shows all the ionic substances as ions and shows the correct state of each substance.
Magnesium react with hydrochloric acid according to the equation :
Mg(s)+2HCL(aq)----->MgCL2(aq) +H2(g)
This demonstration can be used to illustrate the characteristics reactions of metals with acid , a single replacement reaction ,or to demonstrate the generation of hydrogen gas.
Can someone please answer this?
Answer:
B) go look on the periodic table for the atomic number
Explanation:
The atomic number is how many protons is in an atom
Answer:
Either A or B
Explanation: Because I learned it on Edge. :)
An 886 mL sample of Neon gas is at 752 torr and 299 K. What will be the new volume if, with the pressure and amount of gas held constant the temperature is increased to 371 K?
Answer:
[tex]V_2=1099.35mL[/tex]
Explanation:
Hello there!
In this case, according to the given information, it is possible to infer that as both the amount of the gas and the pressure remains the same, we can solve this problem via the Charles' law a directly proportional relationship between the volume and temperature:
[tex]\frac{V_2}{T_2} =\frac{V_1}{T_1}[/tex]
Thus, by solving for the final volume, V2, we obtain:
[tex]V_2 =\frac{V_1T_2}{T_1} \\\\V_2 =\frac{886mL*371K}{299K}\\\\V_2=1099.35mL[/tex]
Best regards!
How many moles are in 30.1 grams of O ? Watch your significant figures.
et
1.88 moles O
1.9 moles O
1.88 g O
2.00 g O
Answer:
1 mole of O contains 16g
x mole of O will contains 30.1 g
= 16x = 30.1
16x/16= 30.1/16
= 1.88 mole of O
the answer is 1.88 mole of O
The mass of this atom is:
u. 3 mass units
b. 4 mass units
c. 6 mass units
d. 7 mass units
e. 11 mass units
A train with an initial velocity of 31 m/s begins accelerating at rate of 0.0705 m/s^2. If the train travels for 180.5s, how far does it travel?
Answer:
v = 43.72 m/s
Explanation:
Given that,
Initial velocity of the train, u = 31 m/s
Acceleration of the train, a = 0.0705 m/s²
Time for which the train travel, t = 180.5 s
We need to find the final velocity of the train. Let it is v.. Using first equation of kinematics to find it such that,
[tex]v=u+at\\\\v=31+0.0705\times 180.5\\\\v=43.72\ m/s[/tex]
So the final speed of the train is equal to 43.72m/s.
WILL MARK BRAINLIEST!!
Need help plsss
6.32 KJ is how much heat is given off
what is the electronic structure of an atom with a proton number 11 and mass number 23
Answer:
1s^2 2s^2 2p^6 3s^1
Explanation:
electron configuration of an element gives description of the distribution of electron in it's orbital of the atom, the superscript symbolize number of electron been hold by them.
The element here is sodium, which is a alkali metal
mass number =23
Number of proton= 11
electron must be seen in thelowest-energy subshell that is available in the the 3s orbital,
Hence, the electronic configuration is
1s^2 2s^2 2p^6 3s^1
Create a model of the atoms of a substance moving through the solid, liquid, and gas states.
At conditions of 785 torr of pressure and 233k a gas occupies a volume of 45.5mL what will be the temperature of the same gas at 745 torr and 634L
Answer:
785
=
233
k
=
45.5
m
L
=
745
=
634
L
=
Explanation:
The picture shows a community living in a dry, grassy area. A few organisms have died off due to lack of a water source. ******Is this an example of an abiotic or biotic limiting factor? WHY
Answer:
brainly blurred the half of the question i cant read it completely
Explanation:
An oxidizing flame resembles the neutral flame slightly, but has an inner cone that is shorter and more pointed with an almost purple color instead of brilliant white true or false
Answer:
True
Explanation:
The answer to this question is true. The oxidizing flame is a flame which is gotten when oxygen is used excessively. The flame is bluish or almost purple in color. And it makes a hissing sound. The flame from this is shorter than the neutral flame. In the neutral flame there is neither the occurrence of oxidation or reduction.
What does the little 2 in 2CO2 mean?
Answer:
it means 2 oxygen atoms in the molecule
Explanation:
Which energy transformation occurs when a match is lit?
A
Chemical energy to heat energy
B
Heat energy to potential energy
C
Electrical energy to heat energy
D
Kinetic energy to potential energy
Answer:
A
Explanation:
the chemical energy in the phosphorous in the match turns into heat energy once the match is struck and starts to combust.
How many milliliters of 0.20 M NaOH must be added to 75 mL of 0.050 M HCl to make a neutral solution?
Answer:
this should help
Explanation:
qestions do you have about plate tectonics
From the deepest ocean trench to the tallest mountain, plate tectonics explains the features and movement of Earth's surface in the present and the past.
Developed from the 1950s to the 1970s, the theory of plate tectonics is the modern update to continental drift, an idea first proposed by scientist Alfred Wegener in 1912 which stated that Earth’s continents had “drifted” across the planet over time. Wegener didn't have an explanation for how continents could move around the planet, but researchers do now: plate tectonics.
Plate tectonics is the theory that Earth's outer shell is divided into large slabs of solid rock, called “plates,” that glide over Earth's mantle, the rocky inner layer above Earth’s core. Earth’s solid outer layer, which includes the crust and the uppermost mantle, is called the lithosphere. It is 100 km (60 miles) thick, according to the Encyclopaedia Britannica. Below the lithosphere is the asthenosphere—a viscous layer kept malleable by heat deep within the Earth. It lubricates the undersides of Earth's tectonic plates, allowing the lithosphere to move around.
Answer:
1. How fast do tectonic plates move? Answer: There are seven major plates: African, Antarctic, Eurasian, Indo-Australian, North American, Pacific and South American
2. What are the factors affecting plate tectonics? Answer: The force that causes most of the plate movement is thermal convection, where heat from the Earth's interior causes currents of hot rising magma and cooler sinking magma to flow, moving the plates of the crust along with them.
3. What 3 things support the theory of plate tectonics? Answer: Modern continents hold clues to their distant past. Evidence from fossils, glaciers, and complementary coastlines helps reveal how the plates once fit together. Fossils tell us when and where plants and animals once existed.
Explanation:
People don't want to live in a warming world so maybe do less things that emit greenhouse gasses.
Answer:
yea that's true
things you can do is: reduce ,reuse, and recycle
reduce the use of air/heat
remove lightbulbs and replace led bulb
drive less
plant a tree
Explanation: