Answer:
b
Explanation:
because its the atom of the same element, the no of protons doesn't change but the mass number changes so we can find the mass number by:
(mass number = atomic no/no of protons + no of neutrons)
here;
mass number given = 65
and we know, no of protons = 29
let no of neutrons = x
hence,
65 = 29 + x
x= 65 – 29
x= 36
hence your answer is b
How many molecules of NO2 are in 0.36 moles?
Answer:
1 mol contains 6.022*10^23 molecules 0.36 moles contain 0.36 * 6.022*10^23 = 2.2 *10^23 molecules
Explanation:
As atoms get smaller,valance electrons are getting closer or farther away from the nucleous.The force of attraction is stronger o weaker so it takes more or lesss energy to remove electrons?
Explanation:
Electrons are closer to the nucleus are in filled orbitals and are called core electrons. More energy which in nucleus called nuclear strOng energy to remove electron thars why its also a way harder too..
______= Speed / Wavelength
Answer:
Frequency
Explanation:
It’s kinda self-explanatory but bascially speed=wavelength times frequency
Answer:
Frequency is Speed divided by Wavelength
Step-by-step explanation:
Don't think there needs to be an explanation for the formula, unless you want the conceptual understanding
explain a mixture of molecules
Answer:
A mixture of molecules is a group of molecules in which there are multiple different elements and atoms, that are in either fixed proportions or random. There are heterogeneous and homogenous mixtures.
Explanation:
How much heat is required to warm 50.0 g of ice from -10.0oC to 0.00oC, melt the ice, warm the water from 0.00oC to 100.0oC, boil the water, and heat the steam to
120.0oC ?
a 209,000 J
b 199,000 J
c 1.67 x 106 J
d 152,000 J
The total heat required to convert the ice to steam is 155,000 J.
The given parameters:
Mass of the ice, m = 50 gInitial temperature of the ice, t = -10 ⁰CFinal temperature of the ice, T = 0⁰C, 100⁰C and 120⁰CSpecific heat capacity of water = 4.184 J/g⁰CHeat of fusion of ice, = 333.55 J/gHeat of vaporization, = 2,230 J/gThe heat required to raise the temperature to 0⁰C is calculated as;
[tex]Q = mc\Delta t\\\\Q_1 = 50 \times 4.184 \times (0 - (-10))\\\\Q_1 = 2092 \ J[/tex]
The heat required to melt the ice is calculated as follows;
[tex]Q_2 = mL_f\\\\Q_2 = 50 \times 333.55 \\\\Q_2 = 16,677.5 \ J[/tex]
The heat raise the temperature to 100⁰C is calculated as;
[tex]Q_3 = 50 \times 4.184 \times (100 - 0)\\\\Q_3 = 20,920 \ J[/tex]
The heat required to boil the water is calculated as follows;
[tex]Q_4 = mL_v\\\\Q_4 = 50 \times 2230\\\\4_4 = 111,500 \ J[/tex]
The heat raise the temperature to 120⁰C is calculated as;
[tex]Q_5 = 50 \times 4.184 \times (120 - 100)\\\\Q_5 = 4,184 \ J[/tex]
The total heat required is calculated as follows;
[tex]Q_t = Q_1 + Q_2 + Q_3 + Q_4 + Q _5 \\\\Q_t = 2092 + 16,677.5 + 20,920 + 111,500 + 4,184\\\\Q_t = 155,373.5 \ J\\\\Q_t \approx 155,000 \ J[/tex]
Learn more about heat capacity here: https://brainly.com/question/16559442
In the equation 2H2 + O2 → 2H20, what are the reactants?
Answer:
2H2 and O2
Explanation:
How many grams of CO2 should be placed in a 250 mL container and -24°C to produce a pressure of 95K PA?
Answer:
About 0.53 g of carbon dioxide needs to be added.
Explanation:
Recall the ideal gas law:
[tex]\displaystyle PV = n RT[/tex]
To determine the amount of carbon dioxide we need, we need to solve for n:
[tex]\displaystyle n = \frac{PV}{RT}[/tex]
Recall that P, V, and T are in atm, L, and K, respectively. R is the universal gas constant.
Convert all values into the correct units:
Volume:
[tex]\displaystyle 250\text{ mL } \cdot \frac{1 \text{ L}}{1000 \text{ mL}} = 0.25 \text{ L}[/tex]
Temperature:
[tex]\displaystyle \begin{aligned} K & =( ^\circ C) + 273.15 \\ \\ & = (-24) + (273.15) \\ \\ & = 249 \text{ K}\end{aligned}[/tex]
And pressure:
[tex]\displaystyle 95 \text{ kPa} \cdot \frac{1.00 \text{ atm}}{101.3 \text{ kPa}} = 0.94 \text{ atm}[/tex]
Substitute and evaluate:
[tex]\displaystyle\begin{aligned} n & = \frac{\left(0.94 \text{ atm}\right)\left(0.25 \text{ L}\right)}{\left(\dfrac{0.08206 \text{ L-atm}}{\text{mol-K}}\right)\left(249\text{ K}\right)} \\ \\ & = 0.012 \text{ mol CO$_2$}\end{aligned}[/tex]
Convert moles to grams:
[tex]\displaystyle 0.012 \text{ mol CO$_2$} \cdot \frac{44.01 \text{ g CO$_2$}}{1 \text{ mol CO$_2$}} = 0.53 \text{ g CO$_2$}[/tex]
In conclusion, about 0.53 g of carbon dioxide needs to be added.
7. Which white blood cells help to get rid of good cells that have been infected by a pathogen? *
(2 Points)
A. T cells
B. B cells
Answer:
B cells and T cells. The B cells produce antibodies that are used to attack invading bacteria, viruses, and toxins. The T cells destroy the body's own cells that have themselves been taken over by viruses or become cancerous.
Explanation:
100 POINTS PLEASE HELP
1. What is the molar mass of NaOH?
2.How many atoms are in 3.35 moles of Aluminum?
3.How many moles of CO2 gas are in a 101.25 L container filled with CO2 gas?
4.What is the mass of 13.7 moles of N2 gas?
5.How many moles are in 78.5 molecules of CaCO3?
Answer:
1) Molar mass of NaOH can be calculated by taking the atomic mass values in the periodic table. Na (Sodium) = 22.98g/mol, O (Oxygen) = 16g/mol, H (Hydrogen) = 1.01g/mol
Add all the the mass values together for NaOH's molar mass, so (22.98 + 16 + 1.01) = 39.99 or round it to 40g/mol
2) To find the atoms from the moles, you just multiply Avogadro's number (6.02 x 10^23) by the moles.
So 3.35 x (6.02 x 10^23) = 2.0167 x 10^24 atoms are in 3.35 moles of aluminum
3) If the question is asking under standard temperature and pressure, we know that if we divide the volume by the molar volume of a gas (which is 22.7 in standard temperature and pressure), we can get the moles.
So 101.25L / 22.7 = 4.46 mol
4) We know that to find the moles, it is the mass divided by the molar mass. If we rearrange the equation to solve for mass, we have to multiply the moles by the molar mass to get there.
Nitrogen's (N) molar mass on the periodic table is 14g/mol, but since Nitrogen is a diatomic element, it would be N2 by itself. So multiply 14 by 2, which will give you 28g/mol. N2's molar mass is 28g/mol.
Now you multiply 13.7 moles by 28g/mol, which will give you 383.6g
5) Now here I think you may have wrote the question wrong. Molecules would be at a way higher number than just 78.5, so I'm first just going to assume you meant 78.5g.
To get the moles from mass, you divide the mass of the compound by its molar mass. Molar mass of CaCO3 can be just calculated using the atomic mass values for each element in the compound (Ca is 40.07g/mol, C is 14g/mol, O3 would be 16 x 3 g/mol or just 48g/mol) and then adding them all together (40.07 + 14 + 48 = 102.07) which would give us 102.7g/mol.
Now, just divide the mass 78.5g by the molar mass 102.7g/mol
78.5/102.7 = 0.764 moles
Now on the offchance that you were actually referring to molecules, and you accidentally typed a different number doing this, you can find out the moles from the molecules by just dividing the number of molecules you have with avogadro's number (6.02 x 10^23)
So it would look something like this:
molecules of CaCO3 / 6.02 x 10^23
Formulate a hypothesis based on something recently observed.
And How could this hypothesis be tested?
Answer:
If garlic repels fleas, then a dog that is given garlic every day will not get fleas. Bacterial growth may be affected by moisture levels in the air. If sugar causes cavities, then people who eat a lot of candy may be more prone to cavities.
Explanation:
draw the lewis structure for co with an arrow representing the dipole moment. refer to figure 10.10 to estimate the percent ionic character of the co bond.
The formation of molecule can easily be shown by drawing Lewis dot structure. Since atom's Lewis dot structure has three dots. Therefore, in below given ways, we can have Lewis dot structure of CO.
What is Lewis dot structure?Lewis dot structure is a way to represent the valence electron of an element in the form of dot. These are mainly beneficial in understanding the chemical formula of covalent compound.
Carbon contains four valence electrons, whereas oxygen has six. Carbon has five electrons but oxygen has seven electrons if just one link is established among carbon and oxygen atoms.
The solitary connection formed in between two atoms is insufficient to form an octet on every atom. A triple bond is required to finish the octet of the each atom in CO. The six electrons shared by these two atoms create a triple bond. The dipole moment arrow will point between carbon to oxygen.
Therefore, in above given ways, we can have Lewis dot structure of CO.
To learn more about Lewis dot structure, here:
https://brainly.com/question/20300458
#SPJ5
PLEASE help in the middle of a test: When table salt forms, which action occurs between the reacting elements?(1 point)
Answer:
don't know if this is what your looking for but it might be a NEUTRILIZATION REACTION.
Answer:
i think its sodium donates an electron to chlorine
Explanation:
Which of the following is true of grinding during
digestion?
A. The process of grinding is a physical change
that takes place in the mouth during digestion.
B. The process of grinding is a chemical change
that takes place in the mouth during digestion.
C. The process of grinding is a physical change
that takes place in the small intestine during
digestion
D. The process of grinding is a chemical change
that takes place in the small intestine during
digestion
The process of grinding is a physical change that takes place in the mouth during digestion.
GRINDING:Grinding is one of the processes that occur during the digestion of food molecules into simpler substances.
Grinding of food molecules occurs in the mouth with the aid of the teeth, which is used to chew.
However, the process of grinding is a physical change because it does not result into the formation of new substances or change the chemical constituents of the food.
Learn more about physical change at: https://brainly.com/question/1984022?referrer=searchResults
SERIOUS INQUIRES ONLY
does anyone like pistachio ice cream? fr fr bc like everyone says it’s weird but it’s so good yk like fr. don’t just be answering me for point yo i’ll come after you.
Answer:
I feel it's an extremely underrated Ice cream flavor!
Explanation:
Answer:
it's pretty good
Explanation:
The three nuclides, U-233, U-235, and U-238, are isotopes of uranium because they have the same number of protons per atom and
Answer:
Electrons
Explanation:
Isotopes are atoms which have the same number of protons and electrons but a different number of neutrons. This is also the reason why there are no other changes in the atom but the mass of the specific atom changes.
Hope this helps :)
Merry Christmas. Have fun.
Which statement about electronegativity is incorrect?
A) Within a periodic table group, electronegativity increases from bottom to top.
B) Metals generally have higher electronegativity values than nonmetals.
C) Within a periodic table row, electronegativity increases from left to right.
D) Fluorine is the most electronegative atom of all the elements.
Answer:
A
Explanation:
refer to your text book
Which of the following compounds has the general formula X3Y2?Which of the following compounds has the general formula X3Y2?
There are no above options to choose from so I am giving an example of a X3Y2 formula which is Magnesium nitride, the formula is Mg3N2.
A student is trying to classify an unidentified, solid gray material as a metal or a nonmetal. Which question will best help the student classify the material?.
The question that will best help the student to classify the material is; "is the material malleable or ductile?"
Generally, materials can be classified as metals or non metals. There are properties that are particular to metals and there are properties that are particular to nonmetals and these properties can be used to identify each one of the materials.
The question that will best help the student to classify the material is; "is the material malleable or ductile?" These metallic properties.
Learn more:
https://brainly.com/question/1659592
Missing parts;
A student is trying to classify an unidentified, solid gray material as a metal or a nonmetal. Which question will best help the student classify the material? A. Is the material malleable or ductile? B. Does the material feel hard to the touch? C. Will the material float in water? D. Does the material feel rough or smooth?
Please help me, trying to get all my hw done
Answer:
C. size and shape
Explanation:
Physical properties such as size, shape, color, density, magnetism or the
ability to sink or float can be used to separate the substances in a mixture..
Filtration is when matter is passed through a filter and the larger particles
are separated out. Magnets can be used to separate magnetic matter from
non-magnetic matter in a mixture. Objects that float when placed in water
can be separated from those that don’t by placing the mixture in water.
How far do you think a plate can move in one day?
Find the molar mass of iron (III) nitrate, Fe(NO3)3
Answer:
Hey there are you doing are you doing I will tell you the answer
Can water stay liquid below zero degrees Celsius?
nope it vaporized
.........pls Mark barinlist I
HELP!! Will give brainliness of answered!!
No links!!!!!!
Why does higher temperature increase the reaction rate?
Select one:
The molecules will have higher kinetic energy for higher velocity collisions.
O b. Increasing the temperature causes the reactant molecules to get hotter.
O c. The activation energy will decrease.
O d. Increasing the temperature causes the potential energy in the bonds to decrease.
Check
Answer:
a
Explanation:
Answer:
Im pretty sure it's B, almost 100% sure
Explanation:
why do the noble gases have relatively low electron affinities?
Answer:
Because noble gases have a full octet, their ionization energies are actually quite high. Electron affinity is the amount of energy released when an electron is added to a neutral atom. Because noble gases have stable electron configurations, they have very low electron affinities.
Explanation:
Answer:
Noble gases have a stable outer shell
Explanation:
What is a Chemical Properties and Physical Properties? Please tell me the deffinition of them both.
Answer:
All properties of matter are either physical or chemical properties and physical properties are either intensive or extensive. ... Physical properties can be measured without changing a substance's chemical identity. Chemical properties can be measured only by changing a substance's chemical identity.
Explanation:
If the temperature changes by 100 K, by how much does it change in degrees Celsius?
A. 0 degrees Celsius
B. 100 degrees Celsius
C. 37 degrees Celsius
D. 273 degrees Celsius
Taking into account the degrees Celsius and Kelvin, if the temperature changes by 100 K, by 100 degrees Celsius it change in degrees Celsius.
A degree Centigrade is a unit of temperature (the physical quantity that reveals the level of heat) whose symbol is °C.
On the other hand, the degree Kelvin, whose symbol is K, is the unit of temperature on the scale created by William Thomson Kelvin, in 1848, based on the degree Celsius, he established his zero point (0) at zero absolute (-273.15 ° C). The figure 0 K is equivalent to the theoretical point where gases have no volume. Absolute zero or 0 K is the point where molecules theoretically stop moving. It is the "perfect" cold.
Considering that zero on the Celsius or degrees centigrade (0 ° C) scale is defined as the equivalent of 273.15 K, the conversion from degrees ° C to K is carried out using the following expression:
T(K)= T(°C) + 273.15 K
In this case, if the temperature changes by 100 K, as it is a change in temperature, the numerical value in K units is the same in ° C units.
Then, the correct answer is option B. if the temperature changes by 100 K, by 100 degrees Celsius it change in degrees Celsius.
Learn more about degrees Celsius and Kelvin:
https://brainly.com/question/2800860?referrer=searchResultsWhat is the formula for the binary ionic compound formed between
zinc and nitrogen.
Answer: Zinc nitride (Zn3N2) is an inorganic compound of zinc and nitrogen, usually obtained as (blue)grey crystals. It is a semiconductor. In pure form, it has the anti-bixbyite structure.
Chemical formula: Zn3N2
Space group: Ia-3, No. 206
EC Number: 215-207-3
Appearance: blue-gray cubic crystals
Explanation:
Direction: To compare and differentiate the animal and plant cell base on the presence and absence of certain organelles.Fill in the corresponding organelles in the Venn Diagram
please please answer this question properly i need it!!!!!!
Answer:
hi what are you doing
Explanation:
............
100 ml of nitrogen collected at 27 degree celcius cooled to -73 degree celcius at same pressure.calculate the contraction in volume.
Explanation:
P1. V1/T1 = P2. V2/T2
Apply this
since here, P1 = P2
100 ml / 300 = V2/ 200
==> 100*200/300 = V2
===> V2 = 66.66 ml
Which objects refract light? (Select all that apply.)
the human eye
contact lenses
a magnifying glass
concave mirrors