Answer:
135g Na2CO3
Explanation:
I'm going to assume you mean Molality which is mol solute/kg solvent
Molarity would be mol soute/ L solution
we know we have 155g of water which is .155 kg
essentially we have the equation:
mol/kg = 8.20
we substitute .155 in for kg and get:
mol/.155 = 8.20
Solving this gives mol = 1.271
now we must convert to grams using the molar mass
Molar mass Na2CO3 = 106G/mol
so to cancel moles we multiply:
1.271mol x 106g/mol
= 135g
<h2>Answer:</h2><h3>Part 1:</h3>
Location the element zinc (Zn) on the periodic table:
- Group number : 12
- Period number : 4
- Block : d block
- Element : Transition elements.
<h3>Part 2:</h3>
Protons in an atom of Zn: 30
<h3>Part 3:</h3>
Electrons in a Zn atom: 30
<h3>Part 4 :</h3>
Neutron in an atom of Zn: 35
<h3 />
The enthalpy change for an exothermic reaction is negative because heat is being released, so that takes out two of the responses. Since energy is being released into the surroundings due to the exothermic reaction, the potential energy of the products is lower than that of the reactants. Energy is being put in to make the reaction occur, but then that energy is all being released into the surroundings thus a lower potential energy level for the products
2.47 moles are produce if 85g of N2 react with 180g of Mg
Answer:
C. 1 proton 3 neutrons
Explanation:
A nucleus is more stable if the ratio of the neutrons to protons is between 1:1 and 1:1.5.
Thus the ratios of neutrons to protons for the nuclei are as follows
A- 1:1
B- 1:1
C- 1:3
D- 1:2
Among these ratios, C is the greatest thus the nucleus is the least stable.