Time taken for star to reach Earth = 7.5 years
<h3>Further explanation</h3>
Given
7.5 light years(distance Earth-star)
Required
Time taken
Solution
Speed of light=v = 3 x 10⁸ m/s
1 light years = 9.461 × 10¹⁵ m= distance(d)
So time taken for 1 light years :
time(t) = distance(d) : speed(v)
t = 9.461 × 10¹⁵ m : 3 x 10⁸ m/s
t = 3.154 x 10⁷ s = 1 years
So for 7.5 light years, time taken = 7.5 years
Answer:
yes solution is always a mixture but not all mixtures are solution
Explanation:
A solution.is a homogeneous mixture of substance that have uniform composition throughout
And a mixture hVe twoo or more substances that are not chemically.combine
Answer:
In a neutral molecule, the sum of the bonding valance electrons must be equal. So the products of the negative element and its charges and the positive element and its charge must be equal.
Explanation:
C1×N1 = C2×N2
If we have a 3 valance electrons , the 'A' charge will be either +3 or -5 for a full octet and valance electron in 'B' atoms will mostly result in acquisition of additional electrons (2) for an octet and relative charge of -2.
Balancing the two,
3 × A = -2 × B
To be equal, A = 2 and B = 3
Therefore, A²B³
By looking at a periodic table, we can conclude that the molar mass of lithium is 6.94g, the molar mass of zinc is 65.38g, and the molar mass of gold is 196.97g. Each of these quantities contains 6.02×1023 atoms of that particular element. The units for molar mass are grams per mole, or g/mol.
So The answers are Lithium, Gold, Zinc
Hope This Helps
~Zero~