Answer:
The current temperature is -15° (15° below zero)
Explanation:
The temperature drops 10°:
T-10°
It will reach 25° below zero:
T - 10° = -25°
We add 10° in both members of the equation:
T - 10° +10° = -25° +10°
The equation is simplified as follows:
T = -25° +10°
T = -15°
The integer -15° can be expressed as 15° below zero.
Explanation:
The magnet uses electromagnetic induction meaning it can be readily magnetized and demagnetized (using electricity) when required. When electricity is switched on, it becomes magnetized and lifts an object and when electricity is switched off, it loses magnetism and releases the object.
The magnetic is able to lift heavy objects because it has powerful conductor material (ferromagnetic iron) and the number of electromagnetic coils is many to induce a powerful magnetic force. The electric current, inducing the magnetism, is also powerful.
Learn More:
For more on electromagnetic induction check out;
brainly.com/question/3414535
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Option (a) is correct.
A reducing agent is the one which loses electrons to other substance.
Here, Zn has oxidation number 0 in the L.H.S of the equation, but on R.H.S its oxidation number is +2 i.e. it Zn has donated two of its electrons to
.
Hence, Zn is the reducing agent here.
First of all the ethylamine is base so will be react with water to take the proton from the water (H⁺) , because water is amphoteric will react with bases as acid and acids as a base, so the water in this case will react as an acid and will gives the proton to the base.
In the picture you may see the chemical equation and the structure of the products.
69. The student's skin was obviously warmer than the initial temperature of the bracelet. According to the second law of thermodynamics, heat transfers from a higher temperature to a lower temperature hence heat transfers from the student's skin to the bracelet warming up the bracelet.
70. moles of copper=mass of copper/molar mass of copper
=30.1g/(63.55g/mol)= 0.4736 moles Cu
71. Delta H( heat released) = mCp(deltaT) = 30.1g(0.385 J/gK)(33-19)K = 162.23J
72. Copper is chemically less active than iron.
