It’s c I believe because it says 209 years to complete an orbit so hint yourself ?.....
Answer:
A. cycas
1. it is thick and scaly
2. it grow relatively slowly and have a large, terminal rosette of leaves.
B. bamboo
1. it is very durable
2. it is both flexible and elastic
C. lemna
1. it grows as simple free-floating thalli on or just beneath the water surface
2. it are small, not exceeding 5 mm in length
D. paddy
1. it is variety purity
2. it degree of purity
E. sugarcane
1. it is bear long sword-shaped leaves
2. it's stalks are composed of many segments, and in each joint there is a bud
Answer:
The balanced equation for this reaction will be
→ 
We can see that 1 mole of methane requires 4 moles of fluorine but we have 0.41 moles of CH4 and 0.56mole of F2
So using the unitary method we will get that
- 1 mole of CH4 → 4 mole of 4 mole of fluorine
- 0.41 mole of methane → 4*0.41 = 1.64 mole of fluorine for complete reaction
but we have only 0.56 mole of fluorine that means fluorine is the limiting reagent and the product will only be formed by only this amount of fluorine.
- 4 moles of fluorine → 1 mole of CF4
- 0.56 mole →
= 0.14mole of CF4
- 4 moles of fluorine → 4 moles of HF
- 0.56 mole of fluorine → 0.56 mole of HF
now to find the heat released we have the formula as
DELTA H = n * Delta H of product - n *delta H of reactant
where n is the moles of the reactant and product.
note: since no information is given about the enthalpies of the species we leave it on general equation also you need to add the product side enthalpy of the species present and similarly on the product side.
Answer:
c
Explanation:
1 calorie = 4.184J/g×°C
This also happens to be the specific heat capacity of water, which is the amount of energy it takes to raise the temperature of 1mL of water by 1°C