How does the periodic table help to predict the properties of elements?
A. Elements in the same group have similar properties
B. Elements in the same period have similar properties
C. The number of protons in an atom's nucleus
D. Elements with higher atomic numbers are more reactive
Elements with lower atomic masses are more reactive
A. Elements in the same group have similar properties
How many hydrogens does ethanol have?
A. One
B. Two
C. Six
A. One
If the atomic number of an element is six and the atomic mass is 15, how many neutrons does it have?
A. 6 Neutrons
B. 9 Neutrons
C. 15 Neutrons
B. 9 Neutrons
-5x=-30
x=_
To solve for x, we can divide both sides of the equation by -5:
-5x = -30
x = -30 / -5
x = 6
So, x = 6.
12-x/9=11
x=_
To solve for x, we need to isolate it on one side of the equation.
We start by multiplying both sides of the equation by 9 to eliminate the denominator:
9*(12 - x)/9 = 11 * 9
12 - x = 99
Next, we subtract 12 from both sides of the equation:
12 - x - 12 = 99 - 12
-x = 87
Finally, we multiply both sides by -1 to solve for x:
(-1) * (-x) = (-1) * 87
x = -87
So, x is equal to -87.