238/92U -- 4/2He divided by 234/90?
The element in the missing question mark is . (Use the symbol from the periodic table, not the whole name.)
The missing element in the question mark is Th (Thorium).
To solve this problem, we need to divide the given expression 238/92U - 4/2He by 234/90.
Let's break down the steps to find the answer:
Step 1: Simplify the expression 238/92U - 4/2He
To simplify this expression, we need to find a common denominator for the fractions. The least common multiple (LCM) of 92 and 2 is 92.
238/92U - 4/2He = (238/92) * (90/90)U - 2/2 * He
= (238 * 90)/(92 * 90)U - 2/2 * He
= 21420/(8280)U - 4/2 * He
Step 2: Divide by 234/90
To divide by 234/90, we need to multiply the expression by the reciprocal (inverse) of 234/90, which is 90/234.
(21420/(8280)U - 4/2 * He) * (90/234)
= (21420/(8280))U - 4/2 * He * 90/234
= 21420 * 90 / (8280 * 234)U - 4 * 90 / (2 * 234) * He
= 1937800 / 1938720U - 360 / 468 * He
= 0.99733U - 0.76923He
Therefore, the element in the missing question mark is He (Helium)
To solve the expression 238/92U -- 4/2He divided by 234/90, we need to perform the division and subtraction in the correct order.
Let's perform the division first: 4/2He divided by 234/90.
To divide fractions, we need to multiply the first fraction by the reciprocal of the second fraction.
The reciprocal of 234/90 is 90/234. Multiplying 4/2He by 90/234, we get:
(4/2He) * (90/234) = (4*90) / (2He * 234) = 360 / (2He * 234)
Now we can rewrite the original expression: 238/92U - (4*90) / (2He * 234)
Next, we simplify the division of 238/92U.
Now, since there is no specific number in the expression for the answer, we can't evaluate it further using the given information. The element in the missing question mark cannot be determined.