Answer: A chemical symbol is a one- or two-letter designation of an element. Compounds are combinations of two or more elements. A chemical formula is an expression that shows the elements in a compound and the relative proportions of those elements. Many elements have symbols that derive from the Latin name for the element
What is the molarity of a 300.0 mL solution containing 25.0 g of NaCl?
Answer:
1,43 M
Explanation:
molair mass NaCl = 58,44 g/mol
You need to calculate how many moles 25 g is:
25 g / 58,44 g/mol = 0,4278 mol
0,4278 mol / 0,3 L = 1,43 M
What is (1.20 x 104 m) x (3.070 x 102m)
Which of the following is not an organ in the nervous system?
How many grams of H,O are needed to produce 13 g of NaOH? 2 Na,O2 + 2 H20-4 NaOH + O2
Answer:
This is a typical stoichiometry question.To answer this question you want to get a relationship between
N
a
2
O and NaOH.
So you can get a relationship between the moles of
N
a
2
O
and moles of NaOH by the concept of stoichiometry.
N
a
2
O +
H
2
O ----------------> 2 NaOH.
According to above balanced equation we can have the stoichiometry relationship between
N
a
2
O and NaOH. as 1:2
It means 1 moles of
N
a
2
O is required to react with one mol of
H
2
O to produce 2 moles of NaOH.
in terms of mass 1 mole of
N
a
2
O has mass 62 g on reaction with water produces 2 moles of NaOH or 80 g of NaOH.
62 g of
N
a
2
O produces 80 g of NaOH.
1g of NaOH is produced from 62/80 g of
N
a
2
O
1.6 x
10
2
g of NaOH will require 62 x 1.6 x
10
2
g / 80 of
N
a
2
O
124g of
N
a
2
O.
Explanation:
If sperm and egg cells have half of the number of chromosomes found in other body cells, how do gametes form?
Why is 1/t used as a measure of rate of reaction?
1/t denotes that the reaction order is of the first order. That is, the rate of reaction is directly proportional to the concentration of the reactant. Because scientists use standard units, 1/t equals one divided by one second.
What do you mean by first order reaction ?The term first order reaction is defined as a chemical reaction in which the reaction rate is linearly dependent on the concentration of only one reactant.
In other words, a first-order reaction is a chemical reaction in which the rate varies as the concentration of only one of the reactants changes.
Because a reaction that takes longer to complete is obviously a slower reaction. A fast reaction is one that takes less time to complete. 1/t simply provides a quantitative value for comparing reaction rates.
Thus, 1/t denotes that the reaction order is of the first order.
To learn more about the first order reaction, follow the link;
https://brainly.com/question/12209424
#SPJ2
If the point of the nail can be approximated as a circle with a radius 2.00×10^-3m What is the pressure in MPa exerted on the wall if a hammer strikes the nail with a force of 104 N
Answer:
8.28 MPa
Explanation:
From the question given above, the following data were obtained:
Radius (r) = 2×10¯³ m
Force applied (F) = 104 N
Pressure (P) =?
Next, we shall determine the area of the nail (i.e circle). This can be obtained as follow:
Radius (r) = 2×10¯³ m
Area (A) of circle =?
Pi (π) = 3.14
A = πr²
A = 3.14 × (2×10¯³)²
A = 3.14 × 4×10¯⁶
A = 1.256×10¯⁵ m²
Next, we shall determine the pressure. This can be obtained as follow:
Force applied (F) = 104 N
Area (A) = 1.256×10¯⁵ m²
Pressure (P) =?
P = F / A
P = 104 / 1.256×10¯⁵
P = 8280254.78 Nm¯²
Finally, we shall convert 8280254.78 Nm¯² to MPa. This can be obtained as follow:
1 Nm¯² = 1×10¯⁶ MPa
Therefore,
8280254.78 Nm¯² = 8280254.78 Nm¯² × 1×10¯⁶ MPa / 1 Nm¯²
8280254.78 Nm¯² = 8.28 MPa
Thus, the pressure exerted on the wall is 8.28 MPa
How is wind energy more environmental friendly than heat energy?
Answer:
Wind is an emissions-free source of energy
Overall, using wind to produce energy has fewer effects on the environment than many other energy sources. Wind turbines do not release emissions that can pollute the air or water (with rare exceptions), and they do not require water for cooling.
Explanation:
What does the illustration indicate?
Answer: A
Explanation:
what is the answer to this
Answer:
Explanation:
i may be wrong but i think its b
Answer:
B Ndaira is right for real
Please help it’s already overdue
Answer:
no se amigo esquema no entiendo ingles
Explain why the metals conduct electricity
write in your own words please, don't copy-paste from internet
Answer:
Metals conduct electricity because the electrons inside the metal are relatively free to move. So when electricity is pass through metals, electrons carry electricity and spread it all over the metal. The mobility of electrons is the reason why metals conduct electricity.
The freezing point of a substance is the
at
which it freezes.
Answer:
reff lagay mo yung ilalagay mo
Answer:
Freezing point is the temperature at which a liquid becomes a solid at normal atmospheric pressure. Alternatively, a melting point is the temperature at which a solid becomes a liquid at normal atmospheric pressure.
please help me! (brainliest)
Answer:
It is A
Explanation:
Question pic
(Will make brainliest)
Answer:
c
Explanation:
Answer:
a and c
Explanation:
what creates an electric current in a battery?
A. Atoms dissolving
B. Metals generating
C. Electrons jumping
D. Liquids moving
Answer:
There's a separate chemical reaction happening at the positive electrode, where incoming electrons recombine with ions taken out of the electrolyte, so completing the circuit. The electrons and ions flow because of the chemical reactions happening inside the battery—usually two of them going on simultaneously.
Explanation:
option (B) is right
Metals used in batteries undergo a chemical reaction with the electrolyte and free the electrons. The flow of electrons produces the electric current.
What is the electrical battery?An electric battery can be described as a source of electric power containing of one or more electrochemical cells with external connections.
The positive terminal of the battery is the cathode and its negative terminal is the anode. The negative terminal can be denoted as the source of electrons that will flow via an external electric circuit to the positive terminal.
A redox reaction transforms high-energy reactants into lower-energy products, and the free-energy difference provides the external circuit as electrical energy.
Each cell of the battery contains two half-cells connected in series by an electrolyte containing metal cations. One half-cell includes an electrolyte and the negative electrode and the other half-cell includes an electrolyte and the positive electrode. Cations are reduced at the cathode, while metal atoms are oxidized at the anode.
Learn more about electrical battery, here:
https://brainly.com/question/8745955
#SPJ2
How do parasites affect their hosts?
They help their hosts by consuming or using their cells.
They help their hosts by growing in size.
O They harm their hosts by growing in size.
They harm their hosts by using their hosts as a food source.
Question 4 of 20
A student is performing experiments on a particular substance. Which
statement is an observation of a chemical property of the substance?
A. Its viscosity decreases.
B. It boils.
C. Electricity passes through it.
D. It reacts with acid.
SUBMIT
Answer:
D
Explanation:
Reacting with acid is the only chemical property out of the 4 options. The rest are physical
What does the reaction rate measure?
Answer:
It's C
Explanation:
cuz im goated
HELP ASAP!!!!!! 30 PTS
Mouth, throat, kidney, and stomach cancers can each be linked to a common cause.
Which can be a cause of any of these cancers?
UV radiation
tobacco use
diabetes
sickle cell anemia
Answer:
Tobacco use
Explanation:
Smoking causes cancer, heart disease, stroke, lung diseases, diabetes, and chronic obstructive pulmonary disease (COPD), which includes emphysema and chronic bronchitis. Smoking also increases risk for tuberculosis, certain eye diseases, and problems of the immune system, including rheumatoid arthritis
Answer:
c. Tabaco use
Explanation:
What properties do atoms of the same element share? Select all that apply
atomic number
chemical reactivity
melting point
Answer: your answer is A
Explanation: the atoms has the same properties of the same element as the atomic number.
Why is red tide dangerous to ocean animals?
Answer:
Karenia brevis produces toxins called brevetoxins that affect a variety of marine wildlife. Aquatic organisms can be exposed to brevetoxins in several ways: coming into contact with K. brevis cells or toxins in the water, ingesting cells, inhaling toxins and consuming toxic prey.
Explanation:
30)
Cosmologists believe that the universe is expanding and that it has been expanding since the Big Bang. Astronomers
viewing distant stars see evidence of this expansion in which phenomenon?
A)
Red shift
B)
Blue shift
Gamma pulse
D)
Background radiation
Answer:
i did this so the next person can have brainliest
Explanation:
2 NaOH + H2SO4 ------> 2 H2O + Na2SO4
How many moles of H2O can be produced from 12.5 moles of NaOH?
Explanation:
2moles of NaOH -> 2moles of H2O
so the number of moles r equal.
hence moles of H2O is 12.5
A gas at 127 celsius and 10.0 L expands to 20.0 L. What is the new
temperature in kelvin? (You must convert to Kelvin before calculating
this problem
Answer:
800.3 Kelvin
Explanation:
127°C = 400.15 Kelvin (because 127 + 273.15)
Charles Law:
[tex]\frac{V1}{T1} = \frac{V2}{T2}[/tex] Thus, [tex]\frac{10.0 L}{400.15 K} = \frac{20.0 L}{T2}[/tex]
Then, work out the math algebraically.
T2 = 20.0 / (10.0/400.15)
= 20.0 / 0.02499...
= 800.3 Kelvin
This is assuming the pressure remains constant.
Each cell in an organism contains a set of hereditary information that gets passed from one generation to the next. The genes in all organisms contain instructions needed to make offspring. Which statement describes
heredity in animals?
A Offspring show recessive traits only.
B Offspring receive genetic traits from a single parent only.
C Offspring receive genes with traits that are always physically observable.
D Offspring receive genes from each parent, which contribute to the traits in the offspring.
please help
Answer:
D
Explanation:
Offspring receive genes from both parents, they don't always have a recessive or dominant train but if they do have a dominant trait, it will always show while the recessive will only show if there is no dominant trait. For example: DD, Dr, and rr (D= dominant r = recessive)
Answer:D
Explanation:
i did this one too and it’s right
i really need help with this
Answer:
the process shown here is endocytosis.
Explanation:
endocytosis is a process of taking something inside the cell..
¿Qué es la ciencia? ¿Qué importancia tiene la ciencia para el desarrollo de la humanidad y de la vida? AYUDA PORFAAAAAAAA
Explanation:
La ciencia puede entenderse como una forma que el ser humano encontró para adquirir conocimientos a través de métodos científicos, tecnológicos y basados en estudios, pruebas e investigaciones y no basados en el pensamiento para explicar los fenómenos humanos, de la naturaleza y de la vida.
La ciencia tiene un rol impactante y transformador en la sociedad, todo el conocimiento adquirido por el hombre a través de la ciencia ha transformado para mejor la vida de las personas, generando mayor calidad de vida, salud, educación, sentido crítico, etc.
En el escenario pandémico que vive el mundo actualmente, la ciencia es fundamental, a través de sus estudios e investigaciones que han ayudado en el desarrollo de vacunas efectivas para inmunizar a los humanos contra el virus y salvar vidas.
A chemical reaction that is expected to form 325.0 gof product only forms 123.8 g of product. What is the percent yield of this reaction?
38.1%
61.9%
201.2%
262.5%
Answer:
[tex]\boxed {\boxed {\sf A. \ 38.1 \%}}[/tex]
Explanation:
Percent yield is the ratio of the amount actually produced to how much could theoretically be produced. It is found using this formula:
[tex]\% \ yield = \frac{actual \ yield}{theoretical \ yield} *100[/tex]
For this reaction, the theoretical or expected yield is 325.0 grams. The actual yield is 123.8 grams.
[tex]\% \ yield = \frac{ 123.8 \ g }{325.0 \ g }*100[/tex]
Divide.
[tex]\% \ yield = 0.380923077 *100[/tex]
[tex]\% \ yield = 38.0923077[/tex]
Round to the nearest hundredth. The 9 in the hundredth place tells us to round the 0 to a 1 .
[tex]\% \ yield \approx 38.1[/tex]
The percent yield is about 38.1%
Answer:
38.1%
Explanation:
Convert 6.24 x 10g to standard notation.
Answer:
3.45 x 10^5
Explanation: