The coefficients in a balanced equation can be used as molar ratios, which can act as conversion factors to relate the reactants to the products. These conversion factors state the ratio of reactants that react but do not tell exactly how much of each substance is actually involved in the reaction.
High levels and long periods of stress can increase a person’s risk for many diseases.
True
False
Answer:
true
Explanation:
Does anyone have the chemistry paper 1 higher 2019 mark scheme thank you
no
Explanation:
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2Na + 2H2O --> 2NaOH + H2 How many moles of NaOH can be produced from 7.0 moles of Na Find theoretical yield in moles PLSS HELP ME SOMEBODY 3
Answer:
[tex]n_{NaOH}=7.0molNaOH[/tex]
Explanation:
Hello there!
In this case, according to the given information about this problem, we first consider the given chemical reaction:
2Na + 2H2O --> 2NaOH + H2
Whereas there is 2:2 mole ratio of NaOH to Na; thus, we calculate the required theoretical yield of NaOH in moles as shown below:
[tex]n_{NaOH}=7.0molNa*\frac{2molNaOH}{2molNa} \\\\n_{NaOH}=7.0molNaOH[/tex]
Regards!
An atom of an element contains 12 protons, 12 neutrons, and 12 electrons. This element is in Group A) 1 B) 2 C) 6 D) 18
Answer:
B) 2
Explanation:
This is because the element in discussion is magnesium which has 12 protons and it falls in group 2 (the second column in periodic table)
Which of the following molecules is polar?
CH3F
CF4
CCl4
All of the molecules are polar.
Answer:
CH3F
Explanation:
because if drawn out its is asymmetric
what is acid? Explain it
Answer:
An acid is a chemical that is posining or sometimes not
Explanation:
This is the best I could explain brainliest
Describe the surgery that would be used to treat Kayla's condition. What are the risks of the surgery?
Answer:
By pass surgery.
Explanation:
Kayla is suffering with blocked artery. The doctors have tried to open up her blocked artery with injecting the stunt by angioplasty process. The treatment had been unsuccessful and she is still complaining chest pain. The next move of the doctors would be by pass surgery which will open up the blocked artery. There are many risks involved in this surgery. The patient may get into coma due to excess bleeding or she may die if her blood pressure shoots up during surgery.
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Answer:
The answer is D
Explanation:
Answer:
A. Heater will only become warm when switch is closed.
Explanation:
Switches are used to control the flow of electrons (basically electricity). If you look at the other trials, you see that when switch is open, the bulb or fan does not run cuz no electricity can get to them. But when switch is closed, electricity gets to them. Thus, they will experience similar thing with the heater I assume cuz they have not said anything about battery voltage or anything preventing heater from heating.
How many moles of gas would you have if you have a volume of 38.0 L under a pressure of 1430 mmHg at standard temperature
Answer: There are 3.2 moles of gas if you have a volume of 38.0 L under a pressure of 1430 mmHg at standard temperature.
Explanation:
Given: Volume = 38.0 L
Pressure = 1430 mm Hg (1 mm Hg = 0.00131579 atm) = 1.9 atm
Temperature = 273.15 K
Using ideal gas equation, the moles of gas will be calculated as follows.
[tex]PV = nRT\\[/tex]
where,
P = pressure
V = volume
n = no. of moles
R = gas constant = 0.0821 L atm/mol K
T =temperature
Substitute the values into above formula as follows.
[tex]PV = nRT\\1.9 atm \times 38.0 L = n \times 0.0821 L atm/mol K \times 273.15 K\\n = \frac{1.9 atm \times 38.0 L}{0.0821 L atm/mol K \times 273.15 K}\\= 3.2 mol[/tex]
Thus, we can conclude that there are 3.2 moles of gas if you have a volume of 38.0 L under a pressure of 1430 mmHg at standard temperature.
Can the excess reactant control the percentage yield
Global average temperature increases when energy absorbed by the surface ___?
increases
decreases
remains the same
Answer:
Increases
Explanation:
The main reason of increase earth's temperature is the increase of CO2 gas in the air which causes global warming and the ice burgs in the poles are getting melted and it results in the increase of the sea water level.
This is the main our problem in the future.
If a .05 gram pill of aspirin is dissolved into 50 grams of water, what is the
percent by mass concentration of aspirin in water?
Answer:
0.10 % w/w
Explanation:
The percent by mass (%w/w) is defined as one hundred times the ratio between the mass of solute (In this case aspirin, 0.05g) and the mass of solution (Mass solute + mass of water = 0.05g + 50g = 50.05g). The percent by mass is:
0.05g Aspirin / 50.05g * 100 =
0.10 % w/w
An airplane starts at rest and accelerates down the runway for 20 sec. at the end of the runway, its velocity is 80m/sec. What is its acceleration?
Answer:
The correct answer is - 4 m/s
Explanation:
Given:
time = 20 sec
velocity= 80 m/s
Accelaration = ?
Solution:
formula for the accelaration can be drive from the for
vi = vf + ( a.t)
0 m/s (rest) = 80 m/s + (a.20s.-1)
a.20.-1= -80,
we check if this is true;
0 m/s= 80 + -80 = 0 so its true.
so a.20.-1= -80,
a= 80/20 ,
Thus, the correct answers a = 4 m/s
cultura de Australia ?
La cultura de Australia es una cultura occidental derivada principalmente de Gran Bretaña, pero también influenciada por la geografía única del continente australiano, la diversa aportación de aborígenes, isleños del Estrecho de Torres y otros pueblos de Oceanía. ... Los australianos son generalmente relajados, abiertos y directos.
Can someone help me with this?
A student places three ice cubes in a beaker and allows them to partially melt. If she measures the temperature of the water in the beaker, what will she most likely observe? Explain your answer.
**Check for proof photos at the bottom.**
**Answers are in bold.**
__________________________________________________________
A student places three ice cubes in a beaker and allows them to partially melt. If she measures the temperature of the water in the beaker, what will she most likely observe? Explain your answer.
She will see that the temperature of the water is 0 degrees Celsius and it stays at that temperature until all the ice cubes completely melt.
__________________________________________________________
Use the table on the right to calculate each required quantity. Record values to 3 significant digits.
First answer: 35.8 kJ
Second answer: 871 g
Third answer: Fe
__________________________________________________________
An iron sphere with a mass of 75.00 g is heated to a temperature of 385.0°C. It is then placed in a beaker containing 150.0 g H2O at 100.0°C.
First answer: 339 kJ
Second answer: 9.02 kJ
Third answer: No
__________________________________________________________
A sample of water has a mass of 100.0 g. Calculate the amount of heat required to change the sample from ice at –45.00°C to water vapor at 175.0°C. Relevant constant values are given to the right.
First answer: 325 kJ
Second answer: boiling the water
__________________________________________________________
Identify the correct description for each part labeled on the diagram.
A: ✔ heating solid
B: ✔ melting
C: ✔ heating liquid
D: ✔ boiling
E: ✔ heating gas
F: ✔ melting point
G: ✔ boiling point
Where are the particles closest together?
✔ A
Explanation:When ice partially melts, the surrounding water remains at 0° Celsius. This is because ice melting only involves the water molecules overcoming intermolecular forces, or forces holding molecules together. The water molecules themselves aren't increasing in kinetic energy when turning into liquid. Since temperature measures kinetic energy, the temperature in this case, remains at 0°.
To find how much energy it takes to cause a phase change in a substance, you must find the number of moles, and determine whether to use ΔHvap and ΔHfus. ΔHvap is used to show how much energy is involved in evaporation and condensation, and ΔHfus is the same but used for melting and freezing. To find number of moles of a given substance, use the formula: mass of given substance divided by atomic mass. Both numbers have to use the same mass unit. Then, multiply number of moles by ΔHvap or ΔHfus to get kJ.
In a heating curve graph, the flat lines represent no change in energy, or the phase changes. The steep lines are change in energy, which are either heating or cooling. The bottom line is a heating/cooling solid. A heating/cooling solid is the coldest phase, which is why the line is at the bottom.
Here are photos of Edge to make things easier.
Why does breaking up a solid reactant increase the rate of reaction?
Question 2 options:
a)
it creates more solid
b)
it increases the concentration
c)
it increases the surface area
d)
it creates more energy
Answer:
B...
Explanation:
sorry if i got it wrong, mines was right..B 1. What type of signal is represented by discrete values?
A analog
B continuous
C sine wave
D digital
Answer:
digital signal is the answer
What is scientific method? a. A plane for forming a scientific hypothesis. b. A technique for carrying out a scientific explement c. A formula for analyzing scientific data d. An organized way to test scientific ideas
Answer:
d. An organized way to test scientific ideas
Explanation:
Science can be defined as a branch of intellectual and practical study which systematically observe a body of fact in relation to the structure and behavior of non-living and living organisms (animals, plants and humans) in the natural world through experiments.
An experiment can be defined as an investigation which typically involves the process of manipulating an independent variable (the cause) in order to be able to determine or measure the dependent variable (the effect).
This ultimately implies that, an experiment can be used by scientists to show or demonstrate how a condition causes or gives rise to another i.e cause and effect, influence, behavior, etc in a sample.
A scientific method can be defined as a research method that typically involves the use of experimental and mathematical techniques which comprises of a series of steps such as systematic observation, measurement, and analysis to formulate, test and modify a hypothesis.
A hypothesis is considered to be tentative or an educated guess and can be defined as a testable explanation for an observation or a scientific problem. An example of a hypothesis is saying, Corona virus is caused by the introduction of the "5G" technology.
Thus, for any hypothesis to be true and acceptable in science, it must be supported by observations and the results of control experiments; this give rise to factual informations, theories and by extension solutions to problems.
In conclusion, we can deduce from the aforementioned paragraphs that a scientific method is simply an organized way to test scientific ideas and hypothesis.
The compound consists of 40.1% carbon, 6.6% hydrogen and 53.3% oxygen. Its relative density with respect to hydrogen is -15. What is the formula of the compound?
Answer:
https://socratic.org/answers/220339
this is the answer , my grandpa create this page
Explanation:
Gas particles that are at low temperature and high pressure and are close to changing phases are considered:
a)Real Gases
b)Ideal Gases
c)Both Ideal and Real Gases
You have 1.29 moles of hydrogen peroxide, H2O2. How many grams is this?
Answer:
m = 43.87 grams
Explanation:
Given that,
Number of moles, n = 1.29 moles
The molar mass of H₂O₂ is, M = 34.0147 g/mol
We know that,
[tex]n=\dfrac{m}{M}[/tex]
Where
m is mass of H₂O₂
So,
[tex]m=n\times M\\\\m=1.29\times 34.0147 \\\\m=43.87\ g[/tex]
So, there are 43.87 grams of H₂O₂.
1. Which of the following factors does not affect the voltage produced in a voltaic cell?
A. concentrations of lons
B. pressure
C. metal of the electrodes
The voltage is the potential difference between the two ends of the conductor. The factor that does not affect the voltage produced in a voltaic cell is pressure. The correct option is B.
What is a Voltaic cell?A voltaic cell uses a chemical reaction to convert electrochemical energy to electrical energy. It consists of cathode and ions which flow through the cathode and anode.
The pressure has nothing to do with the Electrochemical devices.
The factor does not influence the voltage produced in a voltaic cell is pressure. The correct option is B.
Learn more about Voltaic cell.
https://brainly.com/question/1370699
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What’s the charge on the ions formed by group 7 elements? (GCSE)
PLEASE ANSWER QUICKLY!! LOTS OF POINTS!❤
Phosphorous has two common isotopes, phosphorous - 30 and phosphorous - 31. Using the periodic table what can you infer about these two isotopes?
Explanation:
The idea here is that you need to use the Periodic Table of elements to find the mass number of the most common isotope of phosphorus, P.
The reaction is run at two temperatures where temperature 1 is lower than temperature 2. Which relationship is correct for either rate constant (k1 or k2) or activation energy (Ea,1 and Ea,2)
Answer:
The answer is "[tex]K_1 < K_2[/tex]"
Explanation:
In the given question, the value of the [tex]K=Ae^{-\frac{Ea}{RT}}[/tex] and the [tex]T_1 <T_2[/tex]is the rate value which is the constant that is [tex]K_2>K_1[/tex]. As per the temperature value when its increase rate is constantly increasing. [tex]E_a[/tex] is activation energy it is not dependent on the temperature that why the answer is [tex]K_1 < K_2[/tex].
1. How are rates of chemical change expressed?
Explanation:
The rate of reaction is expressed as decrease in concentration of reactant or increase in product per unit time. It is also defined as the increase of concentration of the product per second.
Answer:
Explanation:
Reaction rate, in chemistry, the speed at which a chemical reaction proceeds. ... It is often expressed in terms of either the concentration (amount per unit volume) of a product that is formed in a unit of time or the concentration of a reactant that is consumed in a unit of time.
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how many moles are in 456 g of CaCO3
Answer:
4.556 moles
Explanation:
mole=mass/ molar mass
mole= 456/100.08
mole= 4.556
What is the rate of diffusion of NO gas to CO gas?
Answer:
0.97
Explanation:
Let R₁ represent the rate of diffusion of NO.
Let R₂ represent the rate of diffusion of CO.
Molar mass of NO (M₁) = 14 + 16 = 30 g/mol
Molar mass of CO (M₂) = 12 + 16 = 28 g/mol
Thus, the rate of NO to CO can be obtained as follow:
R₁ /R₂ = √(M₂/M₁)
R₁ /R₂ = √(28/30)
R₁ /R₂ = √(28/30)
R₁ /R₂ = 0.97
R₁ : R₂ = 0.97
NO : CO = 0.97
Therefore, the rate of diffusion of NO to CO is 0.97
Why is copper a popular mineral? Is it in danger of depletion? Use details to support your answer.
Answer:
yes it is a danger.Copper doesn't break down in the environment, leading to its accumulation in plants and animals. Absorption of some copper into the body is essential for human health. Acute industrial exposure to copper fumes, dusts or mists can result in chronic copper poisoning.Copper is a mineral and an element essential to our everyday lives. It is a major industrial metal because of its high ductility, malleability, thermal and electrical conductivity and resistance to corrosion. It is an essential nutrient in our daily diet.