Place a burning splint near the opening of a test tube. If a popping noise occurs, it's probably hydrogen. Place a glowing splint in the test tube, and if it reignites, it could be oxygen. Place a burning splint into a test tube, and if it goes out, it could be carbon dioxide.
The coefficient for hydrogen in the balanced equation of solid molybdenum(iV) oxide with gaseous hydrogen is 2
Explanation
Coefficient is defined to as a number in front of a chemical formula in a balanced chemical equation.
The reaction of molybdenum (iv) oxide with gaseous hydrogen is as below,
MoO2 + 2 H2→ Mo +2 H2O
From balanced equation above the coefficient for H2 is 2 since the number in front of H2 is 2
Answer:
83°C
Explanation:
The following were obtained from the question:
M = 40g
C = 4.2J/g°C
T1 = 91°C
T2 =?
Q = 1300J
Q = MCΔT
ΔT = Q/CM
ΔT = 1300/(4.2x40)
ΔT = 8°C
But ΔT = T1 — T2 (since the reaction involves cooling)
ΔT = T1 — T2
8 = 91 — T2
Collect like terms
8 — 91 = —T2
— 83 = —T2
Multiply through by —1
T2 = 83°C
The final temperature is 83°C
This is a case of metric system of measurements. The scale of the metric system only differs by a factor of 10. The scale (from greatest to least) is kiloliter, hectoliter, dekaliter, liter, deciliter, centiliter and milliliter. If the unit is 150 dL, and you want to find the equivalent dkL measurement, just move the decimal point 2 decimals places to the left (just follow the scale). The same procedure is done for the other metric units.
150 dL = 1.5 dkL
150 dL = 15 L
150 dL = 1,500 cL
150 dL = 15,000 mL
From the choices, the answer is letter C.
