Answer:
4,10kJ
Explanation:
The reaction of phosphoric acid (H₃PO₄; MW: 97.994 g/mol
) with sodium hydroxide (NaOH; MW: 40 g/mol) is:
H₃PO₄ + NaOH ⇄ H₂PO₄⁻ + Na⁺ + OH⁻
Now, the energy produced for the change in temperature in a calorimeter is:
Q = -H×m×ΔT - C×ΔT
Where H×m×ΔT is the energy absorbed for the system and C×ΔT is the energy absorbed for the calorimeter.
Replacing:
Q = -4.00J/g°C × 103,5g × (31,5°C-22,3°C) - 31,72J/°C × (31,5°C-22,3°C)
<em>H is heat capacity of the system, ΔT is change in temperature, m is total mass of the system: 52,0g + 51,5g = 103,5g and C is calorimeter constant.</em>
<em />
Q = -4100J ≡ <em>-4,10kJ</em>
<em></em>
I hope it helps!
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Answer:
Explanation:
I ) Oxide that dissolves in water to give a solution of pH greater than 7 - Na₂O
It is a metallic oxide and therefore basic in nature . It will dissolve in water to give pH more than 7 .
II )
Acidic oxide insoluble in water - SiO₂ . It reacts with CaO to give CaSiO₃
III ) NO₂
Acid anhydride : SiO₂ It is anhydride of H₂SiO₃ ( H₂O + SiO₂ )
IV ) No effect on moist paper - CO . It is neutral oxide .
V ) Peroxide - Ba O₂
VI ) Amphoteric - ZnO
C. magnetic forces act at a distance
Explanation:
Since he was able to drag the keys along the table by moving the magnet, it shows that magnetic forces acts a distance.
Magnetism is a property exhibited by a wide range of materials.
Around a bar magnet, there are field forces in which the forces of the magnets are felt.
- Magnetic forces are non- contact forces. They don't need to be together to exert their force.
- This is why magnetic forces act at a distance.
learn more:
Electromagnet brainly.com/question/2191993
#learnwithBrainly
Neon? or phosphate or both...
