An element has 2 common isotopes. The first isotope has a mass of 68.926 amu and occurs 60.10% of the time. The second isotope has a mass of 70.925 amu and occurs 39.90 % of the time. Calculate the atomic mass of this element.
Answer:
The atomic mass of element X is 69.724 amu
Explanation:
Given data:
Atomic mass of element X= ?
Percent abundance of X-68.926 = 60.10%
percent abundance of X-70.925 = 39.90%
Solution:
Average atomic mass = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) / 100
Average atomic mass = (68.926×60.10)+(70.925×39.90) /100
Average atomic mass = 4142.4526 +2829.9075/ 100
Average atomic mass = 6972.3601 / 100
Average atomic mass = 69.724 amu.
The atomic mass of element X is 69.724 amu.
Mina is attending cooking school, where she prepares different mixtures of ingredients. She works with both homogenous and heterogeneous mixtures. Today she is using honey and salsa. What kinds of mixtures are these ingredients?
Answer:
Honey is an homogeneous mixture
Salsa is an heterogeneous mixture
Explanation:
Honey is a sweet uniformly colored liquid that can be of a dark variety or of clear golden color. Honey is made in nature by bees from flower nectar and is used as a food additive or sweetener
Honey is a homogeneous mixture because the concentration of the components of honey are uniformly distributed throughout the mixture. Every portion has the same concentration of components
Salsa is a sauce made by mixing chopped tomatoes, onions, chilies, lime juice and seasoning and therefore consists of both solid and liquid components mixed in varying proportion such that part will have continuous that comes in between different types of solid and no two parts have exactly the same composition
Therefore, salsa is an heterogenous liquid.
The horizontal rows on the periodic table are called periods, how many periods are there on the periodic table?
Answer:
Seven
There are seven periods in the periodic table
Answer:
7! :D
Explanation:
Also can you mark me brainliest since I was the first person to answer :p
Think critically which of Mendel principles would apply to mating organisms that have two different alleles for three different traits.
Which of the following is NOT a part of Dalton's atomic theory?
a
Atoms are always in motion.
b
Atoms of the same element are identical.
c
Atoms that combine do so in simple whole-number ratios.
d
All elements are composed of atoms.
Please answer it, its a big test grade.
Answer:
option a = Atoms are always in motion.
Explanation:
John Dalton gives atomic theory in 1808. The main postulates are following,
1 = All mater is composed of indivisible particle called atom.
2 =The atoms of same element are identical, but differ from another element.
3 = The atoms of different elements are combine in fixed proportion and form compound.
4 = Atom can not be created nor destroyed.
5 = Atom is smallest part of an element that take part in chemical reaction.
From above Dalton theory postulates it can be seen that all options are correct except option A.
True or False: Positive ions have more electrons than protons
O True
O False
Answer:
If the atom has more electrons than protons, it is a negative ion, or ANION. If it has more protons than electrons,it is a positive ion.
Explanation:
so yes true
What would happen if you mixed Acid with Water/Lava?
(or even fire)
Answer:
What happens when an acid is mixed with water?
Explanation:
When you mix acid with water, it's extremely important to add the acid to the water rather than the other way around. This is because acid and water react in a vigorous exothermic reaction, releasing heat, sometimes boiling the liquid. When you add water to acid, the water boils and the acid may splatter and splash.
what is the chemical formula for iron oxide
Answer:
Fe₂O₃
Explanation:
PLEASE HELP FAST!!!! I'll give brainliest to the best answer!!
what is a weak and strong alkali?explain with examples,
What is concentrated acid? explain with an example
Answer:
A concentrated acid is an acid which is in either pure form or has a high concentration. Laboratory type sulfuric acid (about 98% by weight) is a concentrated (and strong) acid. A dilute acid is that in which the concentration of the water mixed in the acid is higher than the concentration of the acid itself.
Explanation:
Concentrated acid - Those acids which are pure or have very high concentration in water are called as concentrated acids. For example concentrated Hydrochloric acid (HCl) and concentrated Sulphuric acid are examples of concentrated acids.
The atomic number of an isotope of Bromine-80 is __________.
Answer:
35
Explanation:
The number of protons in bromine-80 is 35, it is the same with the atomic number.
how many g are in 16822 mg?
Answer:
it is jues
Explanation:
1 know
A pure substance with one type of atom is called a(n
Answer:
The correct answer would be Element.
Explanation:
A pure substance can't be broken down into simpler substances by chemical means.
Answer:
An Element
Explanation:
When a substance contains only one type of atom, it is called an element. - (Arizona science center)
I hope that helps ;)
Which of the following is TRUE about a physical change in matter?
O A physical change changes the identity of the substance
O A physical change does not change the chemical formula of the substance
O A physical change has similar characteristics as a chemical change.
A physical change is a change in how the substances react with other substances.
Answer:
B. a physical change does not change the chemical formula of the substance
Explanation:
Physical change does not change the substance or identity of an object
The correct answer is physical change does not change the chemical formula of the substance.
What is a physical change?A physical change is one in which only the physical state of matter is altered. Its chemical characteristics have not changed. A physical change is usually brought about by increasing the temperature or exerting pressure, or both. The original state of matter is restored by reversing the condition, that is, lowering the temperature, lowering the pressure, or both.Physical changes, in other words, are reversible.Learn more about Physical change here:https://brainly.com/question/25014732
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How many protons and neutrons does Polonium-211 have?
Answer:
Protons: 84
Neutrons: 127
Explanation:
The number of protons is the atomic number. The number of neutrons can be found by subtracting the proton number (84) from the isotope number (211)
Polonium-211 is an isotope of polonium which has 84 protons and 127 neutrons.
What are isotopes?
Isotopes are defined as substances having same number of protons but different number of neutrons.Number of protons is characteristic for determining position of elements in the periodic table.
Since,all isotopes have the same number of protons and hence have same position.They have similar chemical properties as they have same number of electrons.
They find applications in the field of nuclear medicine and oil and gas research . There are 2 types of isotopes : stable and unstable
Unstable isotopes are radioactive and are called as radioisotopes.Some of these isotopes are man -made and hence also called as artificial isotopes.Every element has an isotope which is either man-made or natural .
Many properties of isotopes depend on mass which is measured in atomic mass unit. The difference in actual mass and mass number is called mass defect.
Learn more about isotopes,here:
https://brainly.com/question/27475737
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Iron forms rust, expressed as Fe2O3.
Using information from the Periodic Table, what is the mass of one mole of Fe203?
A. 71.85 g
B. 143.70 g
C. 159.70 g
D. 319.40 g
Answer:
it's C. 159.70 g
Explanation:
hopefully that helps
7) What is the density of sulfur dioxide, SO2, at
STP?
Answer:
The density of SO₂ is 2.858 g/L.
Explanation:
Given data:
Density of sulfur dioxide = ?
Given temperature = standard = 273 K
Given pressure = standard = 1 atm
Solution:
Formula used:
PM = dRT
P = pressure
M = molar mass
d = density
R = ideal gas constant
T = temperature
No we will put the values in formula
1 atm × 64.066 g/mol = d× 0.0821 atm.L/mol.K× 273 K
d =64.066 atm.g/mol /22.4133atm.L/mol
d = 2.858 g/L
The density of SO₂ is 2.858 g/L.
I really need help please help me I have 10 minutes to finish
Answer:
200 n
Explanation:
Write the chemical symbol and the charge for the ion with 7 protons and 10 electrons.
I need help on this question
4. If an object has a density of 0.8 g/cm3, will it float or sink in water?
Explanation:
Substances with their density less than the density of water which is 1 g/cm³ will float on it whiles those greater than that of water will sink into the water.
From the question the density of the object is 0.8 g/cm³
Since it's density is less than that of water the object will float on water .
Hope this helps you
How do you define medium and high level profession?according to class 8?
please give this answer quickly
Answer:
Answer: medium level profession can be defined as some one who has moved past entry level but isn't nearing the end . whereas high level profession means a person has moved past entry level and also has reached the end.
Answer:
medium level profession refers to the profession that can be carried out with the help of extra khowledge,skill and vocational training
higher level profession refers to the top level profession that requires higher education and special indeth tranning
A satellite's speed is 10,000 m/s. After 1 min, it is 5,000 m/s. What is the satellite's acceleration?
Answer:
- 83.33 m per second square
Explanation:
Initial velocity u = 10,000 m/s
Final Velocity v = 5,000 m/s
Time t = 1 minutes = 60 seconds
Acceleration a =?
[tex] \because \: a = \frac{v - u}{t} \\ \\ = \frac{5000 - 10000}{60} \\ \\ = \frac{ - 5000}{60} \\ \\ a = - 83.33 \: m {s}^{ - 2} [/tex]
What is a metamorphic rock?
A. A rock that forms from pieces of other rocks that are cemented together
B. A rock that forms from magma or lava as a result of cooling and hardening
C. A rock that forms from another rock as a result of heat, pressure, or both heat and pressure
D. A rock that forms from the remains of plants or animals that are compacted together
Answer: Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means "change in form". The original rock is subjected to heat and pressure, causing profound physical or chemical change. The protolith may be a sedimentary, igneous, or existing metamorphic rock.
Explanation:
Answer: that will be B I am sorry if it is wrong that what it says for me
How many molecules are there in 25.0 grams of water?
Answer:
1.389 mol
Explanation:
[tex]1+1+16=18g/mol.n=mMr=2518=1.389mol.[/tex]
What is the percent by mass of sodium in N A2 S O4
Answer:
32.370%
Explanation:
select the correct answer
Which arrow represents the change of state described
above?
The diagram shows changes of state between solid,
liquid, and gas. The atoms of a substance lose energy
during a change of state. Before the change, the atoms
are close together but are able to slide past one another.
gas
a. M
b. N
c. P
d. Q
Answer:
Q
Explanation:
Answer:
Q
Explanation:
I just took it on ed
The literature value for the density of aluminum is 2.6 g/mL. If an experimenter
calculates a value of 2.2 g/mL, what is their percent error?
Answer:
The answer is
15.38%Explanation:
The percentage error of a certain measurement can be found by using the formula
[tex]P(\%) = \frac{error}{actual \: \: number} \times 100\% \\ [/tex]
From the question
actual density = 2.6 g/mL
error = 2.6 - 2.2 = 0.4
The percentage error is
[tex]P( \% ) = \frac{0.4}{2.6} \times 100 \\ = 15.384615...[/tex]
We have the final answer as
15.38%Hope this helps you
An orbital with n = 4 and ℓ = 2 would be described as
1. 4p.
2. 2p.
3. 2s.
4. 4d.
5. 4s
Answer:
4d
Explanation:
n = 4 and l = 2
shells : S P. D. f
L : 0. 1. 2 3
so when l is 2 it belongs to a D-block elementwrite the name of any two metalloids ?
Answer:
Germanium and Polonium
Explanation:
Can you please mark me brainliest since I was the first person to answer :p
Answer:
Boron and silicon are metalloids.
Hope it helps :)
