A. both permanent magnets and electromagnets.
Explanation:
A permanent magnet can affect and attract any other permanent magnet and even electromagnet.
They also affect any magnetic materials especially metals that can be magnetized.
In the vicinity of such substances, an attractive or repulsive force sets in and they both interact in the presence of the force field in place.
Permanent magnets cannot magnetize non-magnets.
An electromagnet is a magnet produced by the passage of electric current through a wire wound round a metallic core.
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Electromagnet brainly.com/question/2191993
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To find pH, use the following formula ---> pH= - log [H+]
so first we need to calculate the [H+] concentration using the OH concentration. to do this, we need to use this formula--> 1.0x10-14= [H+] X [OH-], so we solve for H+ and plug in
[H+]= 1.0X10-14/[OH-]---> 1.0 x 10-14/ 1.0 x 10-4= 1.0 x 10-10
now that we have the H+ concentration, we can solve of pH
pH= -log (1.0x10-10)= 10
answer is A
A covalent bond? Not sure how much detail you want, sorry
<span>Avogadro's number.
1 mole of any substance, molecule or element is equal to a certain amount of atom.
6.022 x 10^23 is the Avogradro's constant.
Magnesium Oxide is a compound. therefore if you have 30.3 g of it (1 mol), it will have the same number of atoms.
34.69 moles of MgO has 208.9 x 10^23 number of atoms.
2.089 x 10^25 is also a correct answer.</span><span>
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