Answer:
About 7.0 × 10³ J or 7.0 kJ
Explanation:
We want to determine the amount of energy needed to raise the temperature of 67 grams of water from 20°C to 45°C.
We can use the heat equation:
[tex]\displaystyle q = mC\Delta T[/tex]
Where C is the specific heat of water.
Substitute and evaluate:
[tex]\displaystyle \begin{aligned} q & = (67\text{ g})\left(\frac{4.2\text{ J}}{\text{g-$^\circ$C}}\right)\left(45^\circ \text{ C}- 20.^\circ\text{ C}\right) \\ \\ & = (67\text{ g})\left(\frac{4.2\text{ J}}{\text{g-$^\circ$C}}\right)(25^\circ \text{ C}) \\ \\ & = 7.0\times 10^3 \text{ J}\end{aligned}[/tex]
Recall that there are 1000 J in a kJ. Hence:
[tex]\displaystyle \begin{aligned} q & = 7.0\times 10^3 \text{ J} \cdot \frac{1\text{ kJ}}{1000\text{ J}} \\ \\ & = 7.0 \text{ kJ}\end{aligned}[/tex]
In conclusion, it will take about 7.0 × 10³ J or 7.0 kJ of energy to raise the temperature of 67 grams of water from 20 °C to 45 °C.
Which population will increase?
Answer: World 5,306,425,000 6,895,889,000 7,503,828,180
1 China 1,139,060,000 1,341,335,000 1,384,688,986
2 India 873,785,000 1,224,614,000 1,296,834,042
3 United States 253,339,000 310,384,000 329,256,465
Explanation:
true or false a change in state of matter would be considered a physical change
Answer:
true
Explanation:
Because the changes in state of matter would be considered
What volume of 0.826 MKOH solution do you need to make 3.74 L of a solution with a pH of 12.500?
Given that –
pH = 12.5We know that –
pH + pOH = 14Then –
[tex]\qquad[/tex][tex]\bf\longrightarrow pOH = 14 -12.5 [/tex]
[tex]\qquad[/tex][tex]\sf \longrightarrow pOH = 1.5[/tex]
[tex]\qquad[/tex][tex]\sf \longrightarrow [OH^- ] = 10^{-1.5 }[/tex]
[tex]\qquad[/tex][tex]\bf \longrightarrow [OH^-] = 3.16 × 10^{-2}[/tex]
Now the number of moles of KOH need to ensure that concentration of Hydroxide anions is equal to –
[tex]\qquad[/tex][tex]\bf \longrightarrow 3.74\: L \times \dfrac{3.16× 10^{-2}}{1 \: L }[/tex]
[tex]\qquad[/tex][tex]\bf \longrightarrow 1. 18 × 10^{-1 }M [/tex]
Volume of the solution contains the need number of moles of Hydroxide anions –
[tex]\qquad[/tex][tex]\sf \longrightarrow \dfrac{ 1.18×10^{-1} \: moles \: OH^-}{0.826 \: moles \: OH^-}[/tex]
[tex]\qquad[/tex][tex]\sf \longrightarrow 0.143 L [/tex]
[tex]\qquad[/tex][tex]\sf \longrightarrow 0.143 \times 1000[/tex]
[tex]\qquad[/tex][tex]\pink{\bf\longrightarrow 143 mL }[/tex]
______________________________________
4) If an object is traveling at a speed of 400 m/s, how long (in hours) will it take to reach 950.5 km?
A) 3.96 x 10-2
B) 1.43 x 105
C) 6.34
D) 39.6
E) 7.01 x 10-6
Answer:
Answer: 0.66 hours
Explanation:
[tex]{ \rm{time = \frac{distance}{speed} }} \\ \\ { \rm{time = \frac{(950.5 \times 1000) \: m}{400 \: m {s}^{ - 1} } }} \\ \\ { \rm{time = {2376.25 \: s}}}[/tex]
• Remember 1 second accounts for 1/3600 hours
[tex]{ \rm{time = \frac{2376.25}{3600} }} \\ \\ { \rm{time = 0.66 \: hours}}[/tex]
The time taken by object traveling at a speed of 400 m/s to reach 950.5 km distance is 0.66 hr or 39.6 min.
What is average velocity ?
Average velocity is given by the total distance covered by the object in total given time. SI unit of velocity is m/s.
Here in this question it is given that the object is travelling with speed v of 400 m/s and it is to find the time t to reach 950.5 km distance d.
it is known that 1 km = 1000 m
that is 950.5 km = 950500 m
Now, using the relation of speed-distance to find time t to reach 950.5 km distance :
[tex]\begin{aligned}v&=\frac{d}{t}\\t&=\frac{d}{v}\\&=\frac{950500}{400}\\&=2376.25 \text{ s}\end{aligned}[/tex]
Now converting 2376.25 sec into hrs by dividing it by 3600 we get :
2376.25/3600 = 0.66 hr or 39.6 min.
Therefore, the time taken by object to reach 950.5 km distance is 0.66 hr or 39.6 min.
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Calculate the oxidation number for carbon in CH4
Answer:
+4
Explanation:
Oxidation number of neutral compound is 0
Oxidation number of hydrogen in methane is -1
C + (-1×4) = 0
C - 4 = 0
C = 4
1.
Light is a(n) _______wave.
Group of answer choices
A. longitudinal
B. large
C. ocean
D. transverse
Answer: D. transverse
Explanation:
Light is a transverse wave, while sound is a longitudinal wave.
A 4.190 g sample of an oxide of chromium contains 2.179g of chromium, what is its empirical formula?
a. CrO2
b. Cr2O
c. CrO3
d. Cr2O3
I'm not sure but I think it is C. CrO3
The temperature went from 25 to 90 degrees Celsius. What is the CHANGE in temperature?
Answer:
+65 degress ?
Explanation:
I feel like there is more to this question
Need asap thank you
Answer:
c.boron-11
Explanation:
The atomic mass of boron is 10.81 u.
And 10.81 u is a lot closer to 11u than it is to 10u, so there must be more of boron-11.
To convince you fully, we can also do a simple calculation to find the exact proportion of boron-11 using the following formula:
(10u)(x)+(11u)(1−x)100%=10.81u
Where u is the unit for atomic mass and x is the proportion of boron-10 out of the total boron abundance which is 100%.
Solving for x we get:
11u−ux=10.81u
0.19u=ux
x=0.19
1−x=0.81
And thus the abundance of boron-11 is roughly 81%.
How many grams of NaOH is needed to neutralize 90 mL of 1.5 N HCl?
mol = conc × v
= 1.5 × 0.09
= 0.135 moles of HCl
HCl + NaOH > NaCl + H2O
1 mole HCl = 1 mole NaOH
0.135 mol HCl = x
x = 0.135 mol NaOH
mass = mol × molar mass
= 0.135 × 40
= 5.4 g
NaOH = 23 + 16 + 1 = 40 g/mol
I'm not a 100% sure if it's correct
[tex]{ \red {\sf{Define \: Transportational}}}[/tex]
2+x=19
Find x
Easy!!
2+17=19
#hope that helps
Answer:
To find the answer you may
2+17=19
Explanation:
so that is the answer I'm sorry,to not give all the solutions
A block has 73 kg is being pushed and accelerated at rate of 10 m/s. what force is being applied to the block?
730 N
7.3 N
7300 N
730 Kg
Answer:
730 N
Explanation:
force =mass ×acceleration
force= 73kg×10m/s
F=730N
what is science explain
Science can be defined as the study of nature, its behaviors and the
interactions between the various components.
Science is divided into three main branches which are
PhysicsChemistryBiologyScience can also be referred to as the gaining of knowledge through various
methods and verifiable by experiments to ensure it is valid.
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pa help thank yoeee <3333
Answer:
1.c
2.c
3.a
4.b
5.a
i think that's the answer
pls ansswerrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr
Answer: Its C, c is a solid state
the answer :
Hi there !
The answer is "C"
; due to the intermolecular forces of attraction
I don’t have baking powder or all of the 10 subs I found online. I wanna make pancakes any suggestions
Answer:
flour is the main ingredient sooo you need flour,sugar,salt milk,eggs,vegetable oil,vanilla optional.you can add baking powder or baking soda optional.
Select True or False: Consider the reaction N2(g) 3H2(g) 2NH3(g). The production of ammonia is an exothermic reaction. When heat is added to the equilibrium system it will shift to increase the amount of ammonia produced.
Answer:
False
Explanation:
As I like to think of it, equilibrium will shift either 'forwards' (to increase products) or 'backwards' (to increase reactants) to oppose any change in system;
If heat is added, the equilibrium will shift in the direction that reduces heat within the system;
In other words, it will shift in favour of the endothermic reaction, i.e. the reaction where heat is gained by the molecules/atoms and therefore taken out from the system;
If the 'forwards' reaction, producing NH₃, is exothermic (i.e. energy is released in the reaction), then the 'backwards' reaction is endothermic;
So the equilibrium will shift in this direction, which is the reaction of 2 NH₃ molecules producing N₂ and 3 H₂
What kind of intermolecular forces act between two chloramine (NH2CI) molecules?
Explanation:
brain and heart froce acts between two chloramine
Answer:
Dispersion, Hydrogen-bonding, and Dipole forces act between two chloramine (NH2CI) molecules.
Explanation:
Dispersion is exerted between all molecules. Chloramine is polar, therefore dipole forces are present. The molecular geometry of chloramine (NH2Cl) is a trigonal pyramidal, therefore hydrogen-bonding forces are present.
Calculate the mass percentage of each element in aluminum oxide.
Answer:
So, Percentage Composition of Aluminium = 2778×100%=34.62% (approx.) Percentage Composition of Oxygen = 3×1678×100%=61.54% (approx.)
What is the theoretical amount of sodium citrate (Na3C6H5O7) produced if you react 85.0g of citric acid (H3C6H5O7) in excess amount sodium hydroxide? If you actually produced 97.3 g of sodium citrate what is the percent yield?
Answer:
i did not find the amswer sorry
What is the pH when 30.0 ml of 0.005 M HF is mixed with 15.0 ml of 0.01 M NaOH?
Answer:
7.36
Explanation:
my teacher said that was the right answer
Most rain falls _____________________.
on land
in freshwater lakes, rivers, and streams
on the oceans
on the polar ice caps
Answer:
I think it is a)in freshwater lakes,rivers,and stream
Answer:
a) in freshwater lakes, rivers, and streams
#keep learning :)What is the role of starch in the titration reaction?
Answer:
Starch reacts with Iodine in the presence of Iodide ion to form an intensely colored blue complex, which is visible at very low concentrations of Iodine, making it a very good indicator in both direct and indirect lodometric titrations.
Explanation:
hope this helps
WHICH ONE?????????????????? Brainlest
Answer:
I believe it would be C, The number of atoms in the reactants is equal to the number of atoms composing the products
Explanation:
hope this helps! :D
have a miraculous day!! <3
Answer:
The number of atoms in the reactants is equal to the number of atoms composing the products
what happens when you combine hydroxide, chlorine, and 2 drops of h2o
Answer:
Chlorine will react in water to form hypochlorous acid, which can then dissociate into hydrogen and hypochlorite ions, according to Eqn (1). This reaction is very important, as the disinfecting power of HOCl, hypochlorous acid, is about 40–80 times that of OCl−, hypochlorite.Explanation:
CARRY ON LEARNINGAND REMEMBER DO ALWAYS READ AND WRITE
You have 15 grams of of MgSO4, how
many moles of MgSO4 do you have?
A 0.125 Moles of MgSO4
B 0.75 Moles of MgSO4
C 7.5 Moles of MgSO4
D 15.88 Moles of MgSO4
Answer:
C 7.5 Moles of MgSO4
Explanation:
what is the molecular geometry of AsCl3?
Molecules' general shape, as well as bond lengths, bond angles, torsional angles, and any other geometrical factors that affect each atom's position, are revealed by their molecular geometry. The molecular geometry of AsCl₃ is trigonal pyramidal.
Molecule geometry is the study of the three-dimensional configuration of the atoms that make up a molecule. Because the shared pairs of electrons remain localized in a specific location between the nuclei of the involved atoms, covalent molecules have directed bonds.
The arsenic atom is surrounded by 4 regions of electron density which means that it has a steric number equal to 4. According to VSPER Theory, the molecular geometry will be trigonal pyramidal, AX₃E₁.
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2). How are simple carbohydrates, like glucose, used to build starches?
Carbohydrates which include sugars and starches are the primary energy sources produced in plants and used by heterotrophic organisms.
Carbohydrates are composed of a basic chemical formula that typically contains a ratio of one Carbon atom for every two Hydrogen atoms and one Oxygen atom C1H2O1. Basically one carbon atom for every one water molecule Carbon + Water = Carbohydrate.
Monosaccharides or Single Carbon Chain Sugars include Glucose C6H12O6
Disaccharides or Double Carbon Chain Sugars include Sucrose C12H22O11
Combining monosaccharides and disaccharides create Polysaccharides which are complex sugars called starches.
what is the mass in g of 7.009 x 10^21 molecules of Pl3?
Covalent compounds are generally not very hard. Justify the statement.
Covalent compounds are generally not very hard because they are formed by two or more nonmetallic atoms.
COVALENT COMPOUNDS:Covalent compounds are compounds whose constituent elements are joined together by covalent bonds.
Covalent bonding occurs when two or more nonmetallic atoms of an element share valence electrons. This means that covalent compounds will not be physically hard since they constitute non-metals.
Examples of covalent compounds are:
H2 - hydrogenH2O - waterHCl - hydrogen chlorideCH4 - methaneLearn more about covalent compounds at: https://brainly.com/question/21505413