From the following heats of reaction, 2C (graphite) + H2 (g) -->C2H2 (g) H = 227 kJ
6C (graphite) + 3H2 (g) -->C6H6 (l) H = 49 kJ
calculate the heat for the reaction
3C2H2 (g) -->C6H6 (l)
A. 26.7 kJ
B. -26.7 kJ
C. -178 kJ
D. 178 kJ
E. -632 kJ
F. 632 kJ

1. an experiment in your science class lists the materials needed for the lab. it is your job, as a lab partner, to measure out 25 ml of distilled water and 2.5 grams of magnesium. what lab measuring tools would you choose to measure each substance and how would you use each tool to get the correct amounts? be sure to describe the process you would follow step-by-step. (5 points) 2.which of the following is an si base unit for measuring mass? (2 points) ampere gram meter pound 3.which of the following is an si base unit for time? (2 points) decades hours minutes seconds 4.which of the following tools should a scientist use to measure an object in milligrams? (2 points) graduated cylinder pan balance tape measure thermometer 4.which of the following tools should a scientist use to measure an object in milligrams? (2 points) graduated cylinder pan balance tape measure thermometer. 5.a pencil beside a metric ruler. the ruler is scaled from 1 centimeter to 10 centimeters, with markings for millimeters between each number. one end of the pencil is beside the 0 on the ruler, and the pencil point is beside the 5. which of the following measurements is accurate but not precise? (2 points) 5 mm 5 cm 50 mm 50 cm 6. which of the following prefixes represents the largest value? (2 points) giga hector kilo milli 7. which of the following types of graphs is best for plotting the percentages of a whole value in a data set? (2 points) bar graph circle graph histogram line graph

How many liters of oxygen gas, at standardtemperature and pressure, will react with 35.8 grams ofiron metal? 4 fe (s) + 3 o2 (g) → 2 fe2o3 (s)

(04.05 hc) analyze the given diagram of the carbon cycle below. an image of carbon cycle is shown. the sun, a cloud, two trees, one on the left and the other on the right, an animal, lake, and a factory are shown in the image. an arrow is shown from the sun towards the left tree marked a. the sun is marked b. there is an arrow from the air above the clouds, marked c, towards the left tree. an arrow from a location close to the ground marked d points towards dead organisms, which is a label under the animal. an arrow marked e points from the right tree straight up to the clouds. an arrow marked f points from the animal straight up to the clouds. an arrow marked g points from the factory towards the air above the clouds, c. there is an arrow pointing from the air to the lake labeled carbonates in water, an arrow pointing down from dead organisms to fossils and fossil fuels, and an arrow from fossils to the factory. part 1: which compound does c represent? part 2: name a process that could release this compound into the air. part 3: explain how the elements that form it are conserved during the carbon cycle. use complete sentences to explain your answer.