Answer:
Option (C)
Explanation:
A metal detector is usually defined as an instrument that is commonly used to detect the presence of metals in the bags and luggage. It is very widely used in places like airports, railway stations, and other important official places.
This device is generally activated with the help of electromagnetic induction. It contains a single or numerous inducting coils which are connected to the elements placed on the ground surface. These used materials are metallic in nature. Within the region of the electromagnetic field, when any metallic substance enters, it immediately gains energy and thereby transmits an electromagnetic field of its own.
Thus, the correct answer is option (C).
Answer:
D. MgO
Explanation:
We need to look at the charge of element. (Look at a periodic table for this)
Mg, which is Magnesium, has a charge of 2+ because it's in the second column, or group, from the left.
O, which is Oxygen, has a charge of 2- because it's in the second column, or group, from the right.
Since Mg is 2+, it's the cation and since O is 2-, it's the anion. We can put these two elements together into an ionic compound.
Mg^(2+) and O^(2-) becomes Mg2O2, where we can cancel the 2s: MgO.
Thus, the answer is D.
Hope this helps!
Balanced <span>chemical equation :
</span><span>2 P + 5 Cl</span>₂<span> = 2 PCl</span>₅<span>
hope this helps!
</span>
Answer:
A. 0.2395 w/w %
B. 2394ppm
Explanation:
A. To find concentrationin percent by mass of the solution we need to calculate mass of glycerol and mass of water. The formula is:
Mass glycerol / Total mass * 100
<em>Mass glycerol:</em>
The solution is 2.6x10⁻²moles / L. As there is 1L of solution there are 2.6x10⁻² moles of glycerol. In mass (Using molar mass glycerol: 92.09g/mol):
2.6x10⁻² moles of glycerol * (92.09g / mol) = 2.394g glycerol
<em>Mass of water:</em>
998.9mL and density = 0.9982g/mL:
998.9mL * (0.9982g/mL) = 997.1g of water.
That means percent by mass is:
% by mass: 2.394g / (997.1g + 2.394g) * 100 = 0.2395 w/w %
B. Parts per million are mg of glycerol per L of solution. As in 1L there are 2.394g. In mg:
2.394g * (1000mg / 1g) = 2394mg:
Parts per million: 2394mg / L = 2394ppm
