the elements in group 2 have similar chemical properties because each atom of these elements has the same

1. Which phase change is accompanied by the release of heat? A) H20(s)--> H2O(g) B) H20(l) ->H2O(s) C) H20(l)→ H2O(g) D) H

docker41 [41]

Answer:

B, liquid to solid.

Explanation: Since heat is being released, the particles for H2O would clump up. Heat is basically being taken out.

5 0

3 years ago

A solution is made by dissolving 373.5 g of Pb(NO3)2 (molar mass: 331.2 g/mol) in 2.00 × 103 g of water. What is the molality of

hram777 [196]

Answer:
molality = 0.564 m

Explanation:
Molality = number of moles of solute / kg of solvent

1- getting moles of solute:
number of moles = mass / molar mass
we have:
mass = 373.5 g
molar mass = 331.2 g/mol
Therefore:
number of moles = 373.5 / 331.2 = 1.128 moles

2- getting kg of solvent:
mass in kg = mass in grams * 10⁻³
mass in kg = 2 * 10³ * 10⁻³
mass in kg = 2 kg

3- getting molality:
Molality = number of moles of solute / kg of solvent
Molality = 1.128 / 2
Molalty = 0.564 m

Hope this helps :)

7 0

3 years ago

Read 2 more answers

Write the full ionic equation and net ionic equation for sodium dihydrogen phosphate + calcium carbonate, sodium oxilate + calcl

My name is Ann [436]

Answer:

Sodium dihydrogen phosphate + calcium carbonate

Full ionic equation

2 Na⁺(aq) + 2 H₂PO₄⁻(aq) + CaCO₃(s) ⇄ 2 Na⁺(aq) + CO₃²⁻(aq) + Ca(H₂PO₄)₂(s)

Net ionic equation

2 H₂PO₄⁻(aq) + CaCO₃(s) ⇄ CO₃²⁻(aq) + Ca(H₂PO₄)₂(s)

Sodium oxalate + calcium carbonate

Full ionic equation

2 Na⁺(aq) + C₂O₄²⁻(aq) + CaCO₃(s) ⇄ 2 Na⁺(aq) + CO₃²⁻(aq) + CaC₂O₄(s)

Net ionic equation

C₂O₄²⁻(aq) + CaCO₃(s) ⇄ CO₃²⁻(aq) + CaC₂O₄(s)

Sodium hydrogen phosphate + calcium carbonate

Full ionic equation

2 Na⁺(aq) + HPO₄²⁻(aq) + CaCO₃(s) ⇄ CaHPO₄(s) + 2 Na⁺(aq) + CO₃²⁻(aq)

Net ionic equation

HPO₄²⁻(aq) + CaCO₃(s) ⇄ CaHPO₄(s) + CO₃²⁻(aq)

Explanation:

Let's consider two kind of equations:

Full ionic equation: includes all ions and species that do not dissociate in water.
Net ionic equation: includes only ions that participate in the reaction (not spectator ions) and species that do not dissociate in water.

4 0

3 years ago

Magnesium chloride is a salt formed with ionic bonds between one magnesium ion and two chloride ions. Magnesium has two electron

katrin [286]

Answer:

The magnesium atom loses 2 electron to the 2 atoms of chlorine. The 7 valency electrons of each chlorine atom will now be 8 to attain stable configuration. The final compound is written as MgCl2.

Explanation:

Ionic compounds are compound formed from the transfer of electron(s). One atom of the element loses electron(s) while the other atom gains electron(s).

The compound Magnesium chloride is an ionic compound . The bond between an atom of magnesium and 2 atoms of chlorine is an ionic bonding.

The valency electron of magnesium is 2 electron , for the atom of magnesium to attain octet rule, it will easily lose it 2 electrons to the chlorine atoms.

The chlorine atom on the other hand has 7 valency electrons, to attain octet configuration it will most likely gain 1 electron to become stable.

The magnesium atom loses 2 electron to the 2 atoms of chlorine. The 7 valency electrons of each chlorine atom will now be 8 to attain stable configuration. The final compound is written as MgCl2.

7 0

3 years ago

The overall charge of an atom is ________ if the number of electrons is ________ than the number of protons.

miss Akunina [59]

The overall charge of an atom is positive if the number of electrons is less than the number of protons. Electrons are negatively charged particles while protons are positively charged particles. If there are less electrons as compared to the number of protons in an atom, then naturally the overall charge of the atom would be positive since there are excess protons. Another case would be that the overall charge of an atom is negative if the number of electrons is greater than the number of protons. An atom having more electrons than the number of the protons present would lead to a negative value of the charge since there are excess electrons.

8 0

3 years ago