1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
MArishka [77]
3 years ago
9

Which of the following is a direct observation? A. Music may help plants grow B. The plant is 22cm on day 23 C. two plants must

have died from insects D. The plants will likely grow 2cm per day 2. A new fertilizer is being tested to determine if it will help plants grow. Each day the researcher gives fertilizer to half the plants and measures the height of all plants. This is an example of which step in the scientific method? A. Ask a question B. Conduct the experiment C. Form a conclusion D. From a hypothesis
Chemistry
2 answers:
Marizza181 [45]3 years ago
8 0
The answer is B for number 1 because rather than it being an observation it is something that you know for sure happened without guessing. 

the answer is B the researcher is actually adding the fertilizer and measuring it.
s344n2d4d5 [400]3 years ago
8 0

Answer:

The correct answer will be options:

1. option-B

2. option-B

Explanation:

<u>Case I </u>

Making an act of direct observation is a way of collecting information in which the observer observes a natural behavior in its natural environment without making assumptions.

In the given questions, the case of direct observation will be when the height of the plant is measured on 23rd day. Thus, Option-B is the correct answer.

<u>Case II </u>

In the given question, the researcher wants to determine the effect of fertilizer on the growth of the plant so he decides to perform an experiment by giving fertilizers to plants.

This is an act of performing an experiment and thus Option-B is the correct answer.

You might be interested in
A 60g sample of tetraethyl lead, a gasoline additive, is found to contain 38.43g lead, 17.83g carbon and 3.74g hydrogen. Determi
anastassius [24]

Answer:

Empirical formula (which matches the molecular formula) is = PbC₈H₂₀

Explanation:

Our sample: 60 g of tetraethyl lead

In order to determine the compound empirical formula we need the centesimal composition:

(Mass of element / Total mass) . 100 =

(38.43 g lead / 60g ) . 100 = 64.05%

(17.83 g C / 60g) . 100 = 29.72%

(3.74 g H / 60g) . 100 = 6.23 %

These % are the mass of the elements in 100 g of compound. Let's find out the moles of them:

64.05 g / 207.2 g/mol = 0.309 moles

29.72 g / 12 g/mol = 2.48 moles

6.23 g/ 1 g/mol = 6.23 moles

Next, we divide the moles, by the lowest value of them (0.309)

0.309 / 0.309 = 1 mol Pb

2.48 / 0.309 = 8 mol C

6.23 / 0.309 = 20 mol H

There, we have our formula PbC₈H₂₀

6 0
3 years ago
Calculate the specific heat capacity for a 15.3-g sample of gold that absorbs 87.2 J when its temperature increases from 35.0 °C
diamong [38]

Answer:

The specific heat of gold is 0.129 J/g°C

Explanation:

Step 1: Data given

Mass of gold  = 15.3 grams

Heat absorbed = 87.2 J

Initial temperature = 35.0 °C

Final temperature = 79.2 °C

Step 2:

Q = m*c*ΔT

⇒ Q =the heat absorbed = 87.2 J

⇒ m = the mass of gold = 15.3 grams

⇒ c = the specific heat of gold = TO BE DETERMINED

⇒ ΔT = The change in temperature = T2 - T1 = 79.2 - 35.0 = 44.2 °C

87.2 J = 15.3g * c * 44.2°C

c = 87.2 / (15.3 * 44.2)

c = 0.129 J/g°C

The specific heat of gold is 0.129 J/g°C

4 0
3 years ago
A bottle sitting on a table has no forces at all acting upon it.
solong [7]

Answer:

I'm a bit confused on where the question is. Perhaps re-write it in the comments? I'd love to help but this seems more like an answer than a question xD

Explanation:

5 0
2 years ago
Read 2 more answers
Explain the voyage of water molecules as it boils in water
Ierofanga [76]
Hot water rises cold water sinks. So the warm water will stay at the bottom. Transfer of heat through the molecules will make all the water boil
3 0
3 years ago
In the reaction fecl2 + 2naoh fe(oh)2(s) + 2nacl, if 6 moles of fecl2 are added to 6 moles of naoh, how many moles of fecl2 woul
pychu [463]
The balanced chemical reaction would be 

<span>fecl2 + 2naoh =  fe(oh)2(s) + 2nacl

Initial amounts of the reactants are given, so, we need to determine which of the reactants is the limiting reactant and use this amount to determine what is asked. However, what is being asked is how many of the FeCl2 is used in the reaction, showing that it is NaOH that is the limiting reactants. Thus, we just use the initial amount of NaOH and relate the substances by the chemical reaction as follows:

6 mol NaOH ( 1 mol FeCl2 / 2 mol NaOH ) = 3 mol FeCl2

Therefore, 3 moles of FeCl2 is used up and 3 moles of FeCl2 is also left after the reaction.</span>
5 0
3 years ago
Read 2 more answers
Other questions:
  • Which molecule has polar bonds that do not cancel each other out?
    5·2 answers
  • What does d in organic chemistry stand for
    14·1 answer
  • Non-living parts of an ecosystem (air, water, soil)
    6·1 answer
  • What is the formula of Barium Carbonate?​
    14·2 answers
  • Water can keep engines operating at low temperatures. Which property of water most likely gives it this ability?
    11·1 answer
  • HELP
    11·1 answer
  • What kind of mixture is a solution? Name the different constituents of a solution
    5·1 answer
  • Is the equation 2NO+02 NO, balanced? Explain your answer
    15·1 answer
  • One method for preparing a nitrile is the dehydration of a primary amide.
    7·1 answer
  • Which type of region would be most likely to support chemical weathering?
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!