Answer:
Mass = 15.1 g
Explanation:
Given data:
Number of moles of NaBH₄ = 0.40 mol
Mass in gram = ?
Solution:
Formula:
Mass = number of moles × molar mass
Molar mass of NaBH₄ = 37.83 g/mol
By putting values,
Mass = 0.40 mol × 37.83 g/mol
Mass = 15.1 g
Answer:
c) (12×0.9889) + (13×0.01108)
Explanation:
Given data:
Percentage of C-12 = 98.89%
Percentage of C-13 = 1.108%
Atomic mass = ?
Solution:
98.89/100 = 0.9889
1.108/ 100 = 0.01108
Atomic mass = (12×0.9889) + (13×0.01108)
Atomic mass = (11.8668 + 0.144034)
Atomic mass = 12.01084
Looks like 3*.5 mol of N, or 1.5*.5 N2
<span>convert that to grams.</span>
There are types of lens; concave and convex lens.
The concave lens is a lens which has an inward curve in the middle, that is, the edges of the curve are thicker than the center of the lens, because of this, any light that enter the lens will spread out [diverge]. An image will look smaller and upright when viewed by a concave lens. Image formed by concave lens are usually VIRTUAL.
A concave lens will produce a real image ONLY if the object is located beyond the focal point of the lens.
A convex lens is a converging lens, this is because, the center of the lens is thicker than its edges. Any ray of light that passes through the lens will converge at the middle of the lens at point called principal focus. A convex lens produce a VIRTUAL image when the object is placed infront of the focal point. The virtual image formed is always magnified and upright.<span />
