Answer:
Explanation:
The density of an object is found by dividing the mass by the volume.
The mass is 12.1 grams, but we are not given the volume. Instead, we are told that the water before is 24.2 millilitres and the water after is 28.8 millilitres.
So, the volume was taken using water displacement. We can find the volume by subtracting the initial volume from the volume after the object was added.
- v= with object - initial
- v= 28.8 mL-24.2 mL=4.6 mL
Now we know the mass and volume:
Substitute the values into the formula.
Divide.
Let's round to the nearest hundredth. The 0 in the thousandth place tells us to leave the 3.
1 milliliter is equal to 1 cubic centimer, so the density can also be written as:
The density of the rock is approximately 2.63 grams per cubic centimeter.
Answer:
The coefficient for PH3 is 8. Option D is correct.
Explanation:
Step 1: The unbalanced equation
P2H4(g) ⇆ PH3(g) + P4(s)
Step 2: Balancing the equation
P2H4(g) ⇆ PH3(g) + P4(s)
On the left side we have 4x H (in P2H4), on the right side we have 3x H (in PH3). To balance the amount of H on both sides, we have to multiply P2H4 on the left side by 3 and PH3 on the right by 4.
3P2H4(g
) ⇆ 4PH3(g) + P4(s)
On the left side we have 6x P (in 3P2H4) on the right side we have 8x P (4x in 4PH3 and 4x in P4). To balance the amount of P on bot hsides, we have to multiply 3P2H4 by 2 and 4PH3 also by 2. Now the equation is balanced
6P2H4(g
) ⇆ 8PH3(g) + P4(s)
The coefficient for PH3 is 8. Option D is correct.
Answer:
B)
Explanation:
When an object looses volume it takes up less space, so it would float upward. And since it probably has less density than water it would most likely float.