Answer is: the combined ionic bond strength of CrCl₂ and intermolecular forces between water molecules.
When chromium chloride (CrCl₂) is dissolved in water, the temperature of the water increases, heat of the solution is endothermic.
Dissociation of chromium chloride in water: CrCl₂(aq) → Cr²⁺(aq) + 2Cl⁻(aq).
Energy (the lattice energy) is required to pull apart the oppositely charged ions in chromium chloride.
The heat of hydration is liberated energy when the separated ions (in this example chromium cations and chlorine anions) attract polar water molecules.
Because the lattice energy is higher than the heat of the hydration (endothermic reaction), we can conclude that bonds between ions are strong (the electrostatic attraction between oppositely charged ions).
Answer:
A) positive; added
Explanation:
Based on the reaction:
2NaHCO3(s) + 129kJ → Na2CO3(s) + H2(g) + CO2(g)
<em>2 moles of NaHCO3 requires 129kJ to produce 1 mole of Na2CO3, 1 mole of H2 and 1 mole of CO2.</em>
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That means, the energy must be added being, thus, an exothermic reaction. The exothermic reactions have ΔH >0.
Thus, right answer is:
A) positive; added
Answer:
A rule of thumb is that 1.5 lbs. of baking soda per 10,000 gallons of water will raise alkalinity by about 10 ppm. If your pool's pH is tested below 7.2, add 3-4 pounds of baking soda. If you're new to adding pool chemicals, start by adding only one-half or three-fourths of the recommended amount.
<h2>Complete the table to summarize the properties of the different subatomic particles. </h2>
Explanation:
Atom
It is a smallest particle which cant exist independently.
According To Dalton, atom was indivisible but later on, it was proved that atom can be subdivided into sub atomic particles called electron, proton & neutron.
These subatomic particles have marked properties .
Proton
- It was discovered by E.Goldstein .
- It is positively charged particle
- It is present in nucleus .
- Its mass is equal to 1.6726219 × 10⁻²⁷ kilograms
Neutron
- It was discovered by E.chadwick .
- It is neutral
- It is present inside the nucleus .
- It's mass is equal to 1.674927471×10⁻²⁷ kg
Electron
- It was discovered by J.J Thomson .
- It has negative charge .
- It's mass is equal to 9.10938356 × 10⁻³¹ kilograms
- It is present outside the nucleus in shells .
The answer would be option 4
