I have a test in chem soon can any one help me?
Answer:
I will be glad to
Which of these elements has an electron configuration of [Kr]5s2?
barium
calcium
rubidium
strontium
Strontium has an electron configuration of [Kr]5s²
Further explanationIn an atom there are levels of energy in the shell and sub shell
This energy level is expressed in the form of electron configurations.
Writing electron configurations starts from the lowest to the highest sub-shell energy level. There are 4 sub-shells in the shell of an atom, namely s, p, d and f. The maximum number of electrons for each sub shell is
s: 2 electrons
p: 6 electrons
d: 10 electrons and
f: 14 electrons
From an electron configuration of [Kr]5s² can be concluded :
element is in period 5 (5 = shell)element is group 2(valence electron =2 and block s) has atomic number 38 (Kr = 36 + 2(valence elektron from 5s²)If we look at the periodic system, the elements that meet the requirements in question are Strontium (Sr)
Answer:
D) strontium
If Maria winks exactly 5 times every minute while she is awake and she sleeps exactly 8 hours a day, how many times does Maria wink in a day? winks/day.
Answer:4,800
Explanation:
5 winks a minute, 60 minutes in an hour.
300 winks an hour, 16 hours a day.
4,800.
Answer:
The answer is 4,800 winks per day.
Explanation: There are 24 hours in a day, 24 minus the 8 hours shes asleep is 16. There are 60 minutes in an hour. 5 x 60 is 300. 300 winks an hour multiplied by the 16 hours she's awake is 4,800.
This chart shows characteristics of three different types of atoms.
A 3-column table with one row titled valence electrons in three types of atoms. The first column labeled Atom X has entry 6 valence electrons. The second column labeled Atom Y has entry 2 valence electrons. The third column labeled Atom Z has entry 8 valence electrons.
Which statement is best supported by the information in the chart?
Atom X will donate electrons to Atom Y.
Atom X will accept electrons from Atom Y.
Atom Y will accept electrons from Atom Z.
Atom Z will donate electrons to Atom X.
Atom X will accept electrons from Atom Y.
Answer:
B) Atom X will accept electrons from Atom Y.
Explanation:
because X has 6 electrons and Y has 2 it would make sense for Y to give to X
Which of the following is the best structure for CH2O2? Explain your reasoning.
Answer:
I'm guessing structure 1
Answer:
no
Explanation:
no
Which molecule is the most polarizable?
N₂
O2
CH4
CO2
Answer:
CO2 I was wrong about methane
_____ means to make the body well again
Answers;
A. Body Repair
B. Energy
C. Growth
D. Motion. (Which One is it??)
Answer:
I'm pretty sure it's body repair But it also maybe energy
Explanation:
Answer: A.
Explanation:
the science or study of how man and animals perform tasks and solve certain types of problems involving use of the body.
Hope this helps!....(bruh this was tuff)
You are an employee at "cash for gold" and a customer comes in looking to exchange gold for money. They claim to have 3.47 gram nugget of fold. How many particles (atoms) of gold are in one nugget? With work shown
Answer:
The number of atoms in 3.47 gram nugget of gold is approximately 1.0606 × 10²² atoms
Explanation:
The given mass of gold = 3.47 grams
The molar mass of gold = 196.96657 g/mol
The number of moles of gold in 3.47 grams of gold = 3.47 grams/(196.96657 g/mol)
The number of moles of gold in 3.47 gram nugget of gold = 0.01762 moles
The number of atoms in one mole of gold = 6.02 × 10²³ atoms
The number of atoms in 0.01762 moles of gold = 6.02 × 10²³ atoms/mole × 0.01762 moles
The number of atoms in 0.01762 moles of gold ≈ 1.0606 × 10²² atoms
∴ The number of atoms in 3.47 gram nugget of gold ≈ 1.0606 × 10²² atoms.
Look for other families of ions in the table that follow a pattern similar to that of the polyatomic chlorine ions. Then complete the statement to describe what you find. Select the correct answer from each drop-down menu. Families of ions that contain hydrogen pattern similar to that of the polyatomic chlorine ions. then complete the statement to describe what you find
Answer: Families of ions that contain NITROGEN, SULFUR, and CARBON follow a pattern similar to that of the polyatomic chlorine ions.
Explanation: Plato
Answer:
Answer: Families of ions that contain NITROGEN, SULFUR, and CARBON follow a pattern similar to that of the polyatomic chlorine ions.
Explanation: Plato
Science investigation skills
in your own words describe the process of a physical change
Answer:
A physical change is when the form of an object changes, but the substance stays the same.
Example: Ice melting into water.
what are twoparts of an atom
Solids are usually: equal in density to other phases more dense than liquids less dense than gases
Answer:
more dense than liquids
Explanation:
if there is a sample 50 grams of naoh how many grams are na
Answer:
Which number is IRRATIONAL? A) √12 B) √36 C) √64 D) √144
Explanation:
PLZZ HELP!!
An atom has atomic number 11 and mass number 23. How many electrons does the atom have?
23
22
O 12
O 11
Answer:
12
Explanation:
23-11, why?, because, the difference between atomic and mass number is the neutron number which most a times is equivalent to the electron number.
The __________________ in a chemical formula tells you how many atoms you have of a particular element.
chemical symbols
arrow
subscript
coefficient
I believe the answer is subscript
help quick please?????
Answer:
the core
Explanation:
Answer:
3rd option, the core.
Explanation:
Wich statement best describes the progress of science
Answer:
Scientific ideas are changed when better ones are found.
Explanation:
A chemist is studying an unknown substance. He can break it into its elemental components only by using chemical means.
Based on this observation, how should the unknown substance be classified?
impure substance
solution
mixture
pure substance
Answer:
C, Mixture
Explanation:
Answer:
the correct answer is actually D pure substance
Explanation:
WILL GIVE 5 STAR RATING AND BRAINLIEST IF YOU ANSWER FIRST AND CORRECTLY
What are the total number of elements in C₄H₉OH ?
Convert the following to Celsius
16) 100°K
17) 200°K
18) 273°K
19) 350°K
16) 100- 273= -173°celsius
17) -73°Celsius
18) °Celsius
19) 77°Celsius
A mixture that is uniformly mixed is called __. a homogeneous b heterogeneous c suspension d colloid
Answer:
a. homogenous
Answer: A. homogeneous
Explanation: A mixture that is uniformly mixed is called homogeneous.
Plz mark brainliest:)
Bonus question #2: Unknown element, Element X, exists in nature as two isotopes:
^{351}
351
X has a mass of 350.9196 u and
^{353}
353
X has a mass of 352.9209 u. The average atomic mass of Element X is 351.96 u. Calculate the relative abundance of the two Element X isotopes.
Answer:
Explanation:
your answer is 351.96 i not a 100 per sent right but that should be it
Pleaseee help it’s timed!!
Answer:
voliiviloou
Explanation:
volaiviolu
Answer:
Rows
Explanation:
A student determines the density of an element to be 2.73 g/cm 3 . If the accepted value is 2.70 grams per cm 3 , what is the student's percent error? Identify the element. What is the boiling of this element in Celsius degree
Answer:
Explanation:
percentage error = error x 100 / correct value
= (2.73 - 2.70) x100 / 2.70
= 1.11 %
The element is Aluminium whose density is 2.702 grams / cc
Boiling point of Aluminium = 2519⁰C .
name two units for density? I need help!!!!
Answer:
Density is commonly expressed in units of grams per cubic centimetre. For example, the density of water is 1 gram per cubic centimetre, and Earth ’s density is 5.51 grams per cubic centimetre. Density can also be expressed as kilograms per cubic metre (in MKS or SI units). For example, the density of air is 1.2 kilograms per cubic metre.
Explanation:
Which is a base unit used in the metric system?
Answer:
Quarts Litres Pints Degrees Fahrenheit.ASK for more
Answer:
d
Explanation:
i must be present in a compound for it considered organic
Answer:
Carbon
Explanation:
Organic compounds must contain carbon. They also usually contain hydrogen, oxygen, and often nitrogen and other compounds such as phosphorus.
Nearly all organic compounds contain carbon-hydrogen bonds.
compare and contrast gymnosperms and angiosperms
(JSYK: this is technically biology)
Anyways, a gymnosperm is a plant (usually a tree) that has unprotected seeds, this means it bears no fruits and can include (but are not limited to) connifers, cycads, and the ginko. Angiosperms produce flowers to help fertilization and have protected seeds. They are also likely to produce fruits or vegetables.
Hope this helps, if not, comment down below please!!!
Dashawn has to find the volume of his phone for science
class. He uses a ruler to measure its length, width, and
height and finds the following:
| = 17 cm
w = 7.5 cm
h = 0.8 cm
What is the volume of Dashawn's phone?
Answer: Volume of rectangle = L * W * H
Explanation: Multiply the 3 numbers together
Answer:
volume = L x W x H
V= 17 x 7.5 x 0.8
V = 102 cm^3
Explanation: Multiply the three number.
To find the volume, you multiply length times width times heigh