4x − 8x= −3
Step 1: Simplify both sides of the equation.
4x−8x = −3
4x + −8x= −3
(4x + −8x) = −3 (Combine Like Terms)
−4x = −3
Step 2: Divide both sides by -4.
−4x / −4
−3
- / −4
so your answer will be x= 3/4
.
Answer:
Change in temperature, ΔT = 22.8°C,
Reaction is endothermic.
Explanation:
The amount heat is given by the formula;
q = m×c×ΔT
Where, q is the amount of heat
m is the mass of a substance
c is the specific heat capacity
ΔT is the temperature change.
In this case, making ΔT the subject of the formula, we get;
ΔT = q/m×c
but; q = 868 Joules
m = 15.6 g
c = 2.44 J/g°C
Therefore;
ΔT = 868 J/(2.44 J/g°C × 15.6 g)
= 22.8 °C
Therefore, the temperature change for ethanol is 22.8 °C
This means there is an increase in temperature and therefore the reaction is endothermic.
Answer:
1.5g
Explanation:
According to this question, the amount of copper required to obtain copper sulfide in a 4:1 is 6g. This means that the ratio of copper to sulfur in the compound (copper sulfide) is 4:1.
Hence, to calculate the amount of sulfur required for the reaction to obtain copper sulfide using the above ratio, we say:
1/4 of the amount of copper required (6g)
= 1/4 × 6
= 6/4
= 1.5g of sulfur is required for the reaction to obtain carbon sulfide.
answer: D
Here is a list of the most common ways to speed up a chemical reaction
Increase the temperature (reactions that absorb energy)
Decrease the temperature (Reactions that release energy)