1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
melomori [17]
3 years ago
13

How many elements are in the periodic table?

Chemistry
1 answer:
exis [7]3 years ago
7 0

Answer: 118

Explanation:

You might be interested in
How much energy is required to heat 40g of water from -7 degrees Celsius to 108 degrees Celsius (Lf= 335,000J/Kg for ice)
solniwko [45]
The   energy  required  to heat  40g  of water  from -7 c  to 108 c is
1541000  joules

     calculation

Q(heat)=  M( mass)  x c(specific heat capacity) xdelta t( change in temperature)

M=  40g=  40/1000= 0.04 Kg
C=  335,000 j/kg/c
delta T   (    108 --7= 115  c)

Q  is therefore   =  0.04 g x  335000 j/kg/c  x 115 c  = 1541,000  joules


6 0
3 years ago
Consider the reaction mg(oh)2(s)→mgo(s)+h2o(l) with enthalpy of reaction δhrxn∘=37.5kj/mol what is the enthalpy of formation of
Anni [7]
Answer is: -601,2 kJ/mol
Chemical reaction: Mg(OH)₂ → MgO + H₂O.
ΔHrxn = 37,5 kJ/mol.
ΔHf(Mg(OH)₂) = <span>−924,5 kJ/mol.
</span>ΔHf(H₂O) = <span>−285,8 kJ/mol.
</span>ΔHrxn -enthalpy of reaction.
ΔHf - enthalpy of formation.
<span>ΔHrxn=∑productsΔHf−∑reactantsΔHf. 
</span>ΔHf(MgO) = -924,5 kJ/mol - (-285,8 kJ/mol) + 37,5 kj/mol.
ΔHf(MgO) = -601,2 kJ/mol.
7 0
3 years ago
Read 2 more answers
If lon X has a charge of 2+ and lon Y has a charge of 1-, the chemical the formula of the ionic
Monica [59]

The chemical formula of the ionic compound is XY₂.

<h3>Ionic compounds</h3>
  • Ionic compounds are compounds which are formed from the combination of negatively charged and positively charged ion.
  • Positively charged ions are formed by loss of electrons
  • Negatively-charged ions are formed from gain of electrons

<h3>Formation of ionic compounds</h3>

During the formation of the ionic compound between an ion X that has a charge of 2+ and ion Y has a charge of 1-, two negatively charged ions of Y are required to form a neutral ionic ionic compound when they react with X.

The chemical the formula of the ionic compound they form is as follows;

X²⁺  + 2Y⁻ ---> XY₂

Therefore, the chemical formula of the ionic compound is XY₂.

Learn  more about ionic compounds at: brainly.com/question/13439771

7 0
2 years ago
Calcium is a group 2 element. Chlorine is a group 7 element. They form an ionic compound called
kondaur [170]

Answer:

CaCl2

Explanation:

For every calcium there's 2 chlorine

7 0
2 years ago
How many grams of carbon dioxide are produced from 0.98 mol of Fe3O4?
nexus9112 [7]
Hello

the answer is 43.129310000000004

Have a nice day
4 0
3 years ago
Other questions:
  • Which acceleration will a 20 Newton force cause if applied to a go kart with a 20 kilogram mass? 1 m/s, 20m/s, 10 m/s, 2 m/s
    9·1 answer
  • An element or compound which occurs naturally in the earth is a alloymineralrock.
    7·1 answer
  • How would -174.2 be written in scientific notation?
    8·1 answer
  • In nature, where do fusion reactions take place?
    13·1 answer
  • Assume that you have developed a tracer with first-order kinetics and k = 0.1 s − 1 . For any given mass, how long will it take
    15·1 answer
  • What is the mass of the polypropylene in grams? Assume that 1 lbs = 453.952 grams. Drag and drop the
    9·1 answer
  • The formula for binary ionic compound formed between cesium and fluorine
    12·1 answer
  • How did life begin??✯✯✯✯✯✯​
    7·1 answer
  • I need help with science
    12·2 answers
  • Enthalpy of reaction described for 3Mg+N2----&gt;Mg3N2?
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!