Answer:
The answer is 0.28 g/cm³Explanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\ [/tex]
From the question we have
[tex]density = \frac{2.78}{10} \\ = 0.278[/tex]
We have the final answer as
0.28 g/cm³Hope this helps you
Answer:
p = 0.278 g/cm3
Explanation:
What does it mean when an element has no subscript in a chemical formula?
Answer:
the element has no subscript because it is only one atom of it
Explanation:
If there isn't a subscript, it's presumed that there is only one atom of that element present.
What is subscript?Subscript is defined as a character that is printed slightly below and to the side of another character, commonly a letter or a number. A subscript is a character that is printed slightly below and to the side of another character, commonly a letter or a number. Chemists frequently employ subscripts in their formulations.
There is no number written if there is just one atom. The number is given as a subscript after the atom if there are multiples of a particular kind of atom. The number on the right side of the symbol indicates how many atoms of that element are contained in the molecule. The atomic number of an element is shown as a subscript on the left-bottom corner of a stand-alone symbol.
Thus, if there isn't a subscript, it's presumed that there is only one atom of that element present.
To learn more about subscript, refer to the link below:
https://brainly.com/question/16019591
#SPJ2
4) How does an atom have a charge of -3?
Answer:
When the electrons hit the atoms in the chamber, they cause some of the electrons in the atoms to be stripped or knocked away. ... When one or more electrons is knocked off of an atom, it becomes positively charged. It is now an positive ion. A negative ion can be made by adding an electron to an atom.
Explanation:
7. Think and discuss: As you move down a group, you will recall that the radius increases.
Why do you think an increase in atomic radius would result in a lower
ionization energy?
8. Think and discuss: As you move across a period, you will recall that the radius decreases.
Why do you think a decrease in atomic radius would result in a greater ionization energy?
9. Predict: Electron affinity (EA) refers to the energy released when an electron is added to
an atom. This release of energy is always expressed as a negative value. The greater the
magnitude of the negative value, the greater the attraction for electrons. (An EA of -100
kJ/mol would indicate a stronger attraction for electrons than an EA of -50 kJ/mol.)
How do you think the size of an atom will affect its ability to attract additional electrons?
Answer:
See explanation
Explanation:
7. As we move down the group more shells are added. The addition of more shells means that the atom becomes larger and the outermost electron is now at greater distance from the nucleus and screening effect becomes very important. This greater screening effect of the inner electron reduces the magnitude of effective nuclear charge on the outermost electron thereby lowering the ionization energy.
8. As we move across the period, the effective nuclear charge increases without a corresponding increase in the number of shells. As a result of this, the outermost electron becomes more tightly bound to the nucleus as the atom becomes smaller and atomic radius decreases causing a rise in the ionization energy from left to right across a period.
9. Actually, the smaller an atom is the greater its electron affinity. The smaller the atom is, the more the outermost shell is drawn closer to the nucleus and this means that the atom is better able to attract electrons to itself.
It is due to the size of atom which varies its force of attraction.
As you move down a group, the atomic radius increases due to addition of more number of shells in an atom. This increase in atomic radius would result in a lower ionization energy because the valance electron is farther from the nucleus and held with weak attractive force so less energy is required to remove it.
While on the other hand, as we move from left to right in a periodic table the atomic radius decreases due to addition of more electrons which shrinks the atom and brought the valance shell closer to the nucleus so it becomes harder to remove an electron because the nucleus held these electrons very tightly.
The size of an atom will affect its ability to attract additional electrons because of its force of attraction. Atoms with small radius has more ability to attract electrons due to higher force of attraction as compared to higher atomic radius atoms.
Learn more: https://brainly.com/question/18997340
How long does it take to melt a single brick, how many mins?
Answer:
it depends upon the material used to make the brick
1. Which best represents a compound?
Answer:
D
Explanation:
The one that best represents a compound is answer "D" because you compounds are chemically bonded and are always together.
1375 J of heat energy are added to a 50.0 g sample of copper, which increases temperature from 22.8 C to 94.2 C. Calculate the specific heat of copper.
Answer:
0.385 J/g°C
Explanation:
Using the following formula, the specific heat of an elemental substance can be calculated:
Q = m × c × ∆T
Where;
Q = quantity of heat (J)
m = mass (g)
c = specific heat capacity (J/g°C)
∆T = change in temperature (°C)
Based on the given information, Q = 1375J, m = 50g, initial temperature = 22.8°C, final temperature = 94.2°C, c =?
Q = m × c × ∆T
1375 = 50 × c × (94.2 - 22.8°C)
1375 = 50 × c × 71.4
1375 = 3570c
c = 1375/3570
c = 0.3851
c = 0.385 J/g°C
PLEASE HELP A car burns gasoline to create hot air gas that expands to move the pistons in the engine, which causes the car to be able to move.
What energy transformations occur from the fuel to the movement of the car?
Thermal to mechanical
Thermal to chemical to mechanical
Chemical to thermal to mechanical
Chemical to electrical
Answer:
Chemical to thermal to mechanical
Explanation:
It is because gasoline is chemical energy which turns to thermal. Because it said hot gas which is thermal energy. Then it turns to mechanical for the car to even move.
All seeing eyes:
i know your answer it is the third one (C, chemical to thermal to mechanical)
Explanation:
my all seeing eyes know all the answers
The half-life of carbon-14 is about ____________ years.
Fill in the blank.
Answer:
5730 years
Explanation: for more on radiocarbon dating.) and hence explain why the amount of carbon-14 in the sample decays by half over any period of 5730 years.
A student wants to investigate competition between two organisms. For the investigation, it
is most important that the student should choose organisms that
O require the same resources.
O reproduce at the same rate.
O are both active during the day.
o have the same adaptations.
(help please!!! due today!!!)
Answer:
i think that the answer is B
Explanation:
If a student wants to investigate competition between two organisms in an ecosystem the organisms should have same adaptations and use same resources.
What is an ecosystem?Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.
Energy enters the system through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.
Learn more about ecosystem,here:
https://brainly.com/question/1061425
#SPJ2
help it's chemistry
Answer:
wavelength = wave velocity/frequency.
Explanation:
c
is a constant. It is usually given as
3.00
×
10
8
m/s or
3.00
×
10
10
cm/s rounded to three significant figures.
Wavelength is measured in meters, centimeters, nanometers, etc...).
Frequency has a unit of
1/s
which means
1
cycle per second. It is also given the unit Hertz (Hz) in honor of German physicist Heinrich Hertz who proved the existence of electromagnetic waves.
1
Hz
=
1/s
.
A voltmeter is a device that measures electricity. It can detect the amount of electricity between two electrodes when they are submerged in a solution, such as salt water. Describe how you would find the melting point and the conductivity of the white substances in the beakers. Then, explain how you could identify which substance is salt and which is sugar.
Answer:
Explanation:
To determine the melting point of the unknown white substances. A sample of each of the unknown can be placed in separate capillary tubes and then placed in an adjustable heat source (for example water bath). A thermometer is then placed in the heat source very close to the tube holding the sample. The temperature of the heat source will be adjusted until the solid substance in the capillary tube starts to melt, the temperature at this point is noted as the melting point.
To determine the conductivity of the white substances, an electrolysis experiment is done. A sample each of the unknown substances is dissolved in water. These aqueous solutions are prepared separately. Two electrodes (positively charged anode and negatively charged cathode) are dipped into each of these solutions and an electric current is passed through these solutions, from an energy source (such as batter), through the electrodes (with the electric current flowing from the anode to the cathode). A voltmeter is then connected to this set-up to determine if electricity is been passed through the individual solutions.
The substance that is the salt will be the white substance that has the higher melting point and conducted electricity in the electrolysis set up; this is because NaCl salt is an ionic compound which has a high melting point and conducts electricity when dissolved in water. While the white substance that had a lower melting point and did not conduct electricity will be the sugar; this is because sugar/sucrose is an organic substance that has a low melting point and does not conduct electricity when dissolved in water.
If 10 cubic centimeters of a liquid has a mass of
70 grams, what is its density?
A. 0.7 g/cm3
B. 7 g/cm3
C. 70 g/cm3
D. 700 g/cm
Answer:
V = 10 m³
m = 70 grams
density = ....?
density = m/v
= 70/10
= 7 g/cm³ (B)
What is the unit of temperature on a solubility graph
Answer:
Khfxgkhxxkfhkugxxiufxhfixiyf
Explanation:
Xlufy8fxtukuxfxtu
Answer: Celsius
Explanation:
what are green boxes on periodic tables
Answer:
The basic metal ones?
Explanation:
...
3. What is the electron configuration of the following elements?
Lithium
Calcium
Copper
Strontium
Potassium
sodium
Answer: Lithium ( 3),Calcium (20),Copper (29),Strontium (38),Potassium (19),Sodium (11)
Explanation:
Which statement best describes two functions of blood?
Answer:
flows through your viens and moves to your blood vesils
Explanation:
its how blood operates
If a neutral atom with 88 electrons undergoes 2 rounds of beta minus decay, what will be the new element?
Answer:
The new element will be thorium-226 (²²⁶Th).
Explanation:
The beta decay is given by:
[tex] ^{A}_{Z}X \rightarrow ^{A}_{Z+1}Y + \beta^{-} + \bar{\nu_{e}} [/tex]
Where:
A: is the mass number
Z: is the number of protons
β⁻: is a beta particle = electron
[tex]\bar{\nu_{e}}[/tex]: is an antineutrino
The neutral atom has 88 electrons, so:
[tex] e^{-} = 88 = Z [/tex]
Hence the element is radium (Ra), it has A = 226.
If Ra undergoes 2 rounds of beta minus decay, we have:
[tex] ^{226}_{88}Ra \rightarrow ^{226}_{89}Ac + \beta^{-} + \bar{\nu_{e}} [/tex]
[tex] ^{226}_{89}Ac \rightarrow ^{226}_{90}Th + \beta^{-} + \bar{\nu_{e}} [/tex]
Therefore, if a neutral atom with 88 electrons undergoes 2 rounds of beta minus decay the new element will be thorium-226 (²²⁶Th).
I hope it helps you!
Explain the relationship between protons and ionization energy
Plants prevent a) soil erosion by wind or water b) soil erosion due to a forest station c) The loosening of soil and they bind the soil with the help of the roots
Answer:
The loosening of soil and they bind the soil with the help of the roots
Explanation:
Here, we want to know how plants prevent erosion by wind or water.
The way they do this is by binding the soil with their roots such that it will not be easy for the erosion agent to erode the surface.
How they do this is by making sure that the soil
particles are binded together with their roots which helps to keep the particles of the soil intact and not eroded
Answer:
c
Explanation:
what type of data do you need to find the density of an object
The reaction for the combustion of acetylene is shown. Explain why this reaction is a redox reaction by identifying the oxidation numbers that change, what is oxidized, what is reduced, and what happens to the electrons during the reaction. 2C2H2 + 5O2 → 4CO2 + 2H2O
Answer:
2 C2H2 (g) + 5 O2 (g) → 4 CO2 (g) + 2 H2O (l)
Explanation:
Redox reaction: In this type of reaction, oxidation and reduction reaction occurs simultaneously in same chemical reaction.
2C_2H_2+5O_2\rightarrow 4CO_2 + 2H_2O2C
2
H
2
+5O
2
→4CO
2
+2H
2
O
This reaction is a redox reaction :
Removal of hydrogen or addition of oxygen is termed as oxidation. in above reaction, removal hydrogen from acetylene gives carbon-dioxide.
Removal of oxygen or addition of hydrogen is termed as reduction. in above reaction, removal of one oxygen atom from oxygen molecule with addition of two hydrogen atoms gives water
The oxidation number of carbon in acetylene is -2.
The oxidation number of carbon in carbon-dioxide= +4
Oxidation number of carbon increases after the reaction which means that carbon is getting oxidized.
The oxidation number of oxygen in oxygen gas = 0
The oxidation number of oxygen in water = -2
Oxidation number of oxygen decreases after the reaction which means that oxygen is getting reduced.
The electrons released during oxidation are transferred to the species which are undergoing reduction reaction.
Answer:
Just put this, or something like it:
The oxidation number of carbon changes from -1 to +4.
The oxidation number of oxygen changes from 0 to -2.
Carbon is oxidized.
Oxygen is reduced.
Electrons are transferred from carbon to oxygen.
Explanation:
Which force is stronger? 40 N → or ← 4.218 Newtons
Answer:
40 Newtons
Explanation:
4.218 is not even close to 40 N.
The 40 N force must be the larger force because 40 has a larger magnitude than the 4.218.
Magnitude of a force?
The term magnitude has to do with how large the force is. The larger the force the larger the value that is mentioned.
This implies that the 40 N force must be the larger force because 40 has a larger magnitude than the 4.218.
Learn more about magnitude of force:https://brainly.com/question/1313542
#SPJ2
can anyone help me with this problem :)
The formula of ascorbic acid (vitamin C) is C6H8O6 The recommended dose is 60.0 mg. How many moles are in this dose
Answer:
0.0003 moles
Explanation:
MgC6H8O6 = (60.0mg/1)(1 mol mg/176000mg)
Which is NOT a shape of epithelial cells?
A.Cuboidal
B.Columbar
C.circular
D.squamous
40.0 grams of liquid at its boiling point is
changed to vapor by the addition of 12800
joules of heat. What is the heat of
vaporization of the substance?
Answer:
320J/g
Explanation:
Given parameters:
Mass of the liquid = 40g
Amount of heat added = 12800J
Unknown:
The heat of vaporization = ?
Solution:
The heat of vaporization can be related to heat added by the expression below;
H = mL
H is the heat added
m is the mass
L is the heat of vaporization
Insert the parameters and solve;
12800 = 40 x L
L = [tex]\frac{12800}{40}[/tex] = 320J/g
What mass of oxygen reacts with 12g of magnesium?
Answer:
24g
Explanation:
2×12=24
1mole of Mg react with 2 mooe of O2
Which one does Temperature measure
A. how many particles there are.
B. how fast the particles are moving.
C. how tightly packed the particles are.
D. how large the particles are.
Answer:
B. how fast the particles are moving
Explanation:
Temperature measures the average kinetic energy of system as result of the thermal - heat energy present in the reaction or a body.
Often times, temperature is the degree of hotness or coldness of a body and this translates to an increase or decrease in the molecular speed.
Number of particles in a body is the mass of the body. How tightly packed the particles are corresponds to the density of the body.How many molecules does it take to form 3.00 moles of Silver nitrite (AgNO2)?
Answer:
1.806 × 10²⁴ moleculesExplanation:
The number of molecules of silver nitrite can be found by using the formula
N = n × Lwhere 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
N = 3 × 6.02 × 10²³
We have the final answer as
1.806 × 10²⁴ moleculesHope this helps you
Do nonmetal gases have a lot or a little kinetic energy?
Yes
No
Maybe
Answer:
No they do not have a lot of kinetic energy
What is the molarity of a solution prepared by diluting 43.72 ml of 1.005 M aqueous K2CR2O7 to 500 ml
Answer:
43.72
Explanation:
that is the answer hope u liked it and I did this already along time ago
The molarity of the solution will be "0.088 M".
Given values are:
Volume,
[tex]V_1 = 43.72 \ ml[/tex][tex]V_2 = 500 \ ml[/tex]Molarity,
[tex]M_1 = 1.005 \ M[/tex][tex]M_2 =?[/tex]By using the Dilution principle, we get
→ [tex]M_2 = \frac{M_1 V_1}{V_2}[/tex]
By substituting the given values, we get
→ [tex]=\frac{1.005\times 43.72}{500}[/tex]
→ [tex]= \frac{ 43.9586}{500}[/tex]
→ [tex]= 0.088 \ M[/tex]
Learn more about molarity here:
https://brainly.com/question/19472942