Ūdens tvaiks ir ūdens gāzveida agregātstāvoklī. Tas rodas, ūdenim iztvaikojot vai ledum sublimējoties. Ūdens tvaiks veido daļu no hidrosfēras. Atšķirībā no citiem ūdens agregātstāvokļiem, tvaiks nav redzams. Atmosfēras augšējos slāņos, ūdens tvaikam kondensējoties, rodas mākoņi. Ja tas notiek zemes virskārtas tuvumā, tad veidojas migla.
Ūdens tvaika spiediens atkarībā no temperatūras, bāros.
°C |
0 |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9
|
0
|
0,006351
|
0,006827
|
0,007335
|
0,007876
|
0,008452
|
0,009066
|
0,00972
|
0,010411
|
0,011147
|
0,011929
|
10
|
0,01276
|
0,01364
|
0,014574
|
0,015563
|
0,01661
|
0,017719
|
0,018893
|
0,020135
|
0,021444
|
0,022831
|
20
|
0,024299
|
0,025849
|
0,027481
|
0,029194
|
0,031009
|
0,032926
|
0,034935
|
0,037056
|
0,039289
|
0,041634
|
30
|
0,044102
|
0,046702
|
0,049425
|
0,052290
|
0,055298
|
0,058459
|
0,061763
|
0,065240
|
0,068881
|
0,072694
|
40
|
0,076681
|
0,080872
|
0,085247
|
0,089825
|
0,094618
|
0,099635
|
0,104866
|
0,110342
|
0,116062
|
0,122027
|
50
|
0,128258
|
0,134764
|
0,141534
|
0,148611
|
0,155984
|
0,163662
|
0,171666
|
0,180008
|
0,188685
|
0,19772
|
60
|
0,207101
|
0,21689
|
0,227087
|
0,23759
|
0,248603
|
0,260024
|
0,271852
|
0,28419
|
0,296937
|
0,310295
|
70
|
0,324061
|
0,338336
|
0,353122
|
0,368418
|
0,384325
|
0,400844
|
0,417873
|
0,435616
|
0,453868
|
0,472835
|
80
|
0,492413
|
0,512705
|
0,533711
|
0,555431
|
0,577864
|
0,601011
|
0,624974
|
0,649753
|
0,675347
|
0,701758
|
90
|
0,728882
|
0,757025
|
0,786189
|
0,816168
|
0,847065
|
0,878879
|
0,911816
|
0,94567
|
0,980544
|
1,016743
|
100
|
1,053554
|
1,091793
|
1,131051
|
1,171533
|
1,213239
|
1,256066
|
1,300219
|
1,345596
|
1,392298
|
1,440326
|
110
|
1,489680
|
1,540359
|
1,592567
|
1,646204
|
1,701267
|
1,757861
|
1,815984
|
1,875636
|
1,936920
|
1,999836
|
120
|
2,064383
|
2,130663
|
2,198575
|
2,268323
|
2,339906
|
2,413222
|
2,488476
|
2,565565
|
2,644592
|
2,725658
|
130
|
2,808662
|
2,893705
|
2,980889
|
3,070317
|
3,162090
|
3,254882
|
3,350734
|
3,448625
|
3,549576
|
3,652565
|
140
|
3,757595
|
3,870781
|
3,974791
|
4,087977
|
4,202184
|
4,320469
|
4,440794
|
4,564177
|
4,6896
|
4,818083
|
150
|
4,949624
|
5,083205
|
5,219844
|
5,360563
|
5,503321
|
5,649138
|
5,798014
|
5,950969
|
6,105964
|
6,265037
|
160
|
6,426149
|
6,591341
|
6,760611
|
6,931921
|
7,107309
|
7,286776
|
7,469303
|
7,654888
|
7,844552
|
8,038295
|
170
|
8,235097
|
8,436998
|
8,641958
|
8,849976
|
9,063094
|
9,280290
|
9,500545
|
9,725899
|
9,955331
|
10,188842
|
180
|
10,426433
|
10,668101
|
10,913849
|
11,165715
|
11,421660
|
11,681683
|
11,945786
|
12,214986
|
12,489286
|
12,768683
|
190
|
13,052160
|
13,340735
|
13,634409
|
13,933181
|
14,237051
|
14,546021
|
14,860088
|
15,179254
|
15,503519
|
15,833902
|
200
|
16,169383
|
16,510982
|
16,857680
|
17,209477
|
17,567392
|
17,931425
|
18,301576
|
18,676825
|
19,058193
|
19,445679
|
210
|
19,839283
|
20,239006
|
20,644846
|
21,057825
|
21,475902
|
21,900097
|
22,33245
|
22,974861
|
23,21551
|
23,666217
|
220
|
24,125082
|
24,590066
|
25,061167
|
25,540426
|
26,025803
|
26,519338
|
27,018991
|
27,526802
|
28,04073
|
28,562817
|
230
|
29,093061
|
29,629423
|
30,173943
|
30,726620
|
31,286435
|
31,854408
|
32,429519
|
33,013807
|
33,502244
|
34,204817
|
240
|
34,812558
|
35,429477
|
36,053533
|
36,686767
|
37,328158
|
37,977707
|
38,636433
|
39,304337
|
39,980398
|
40,665636
|
250
|
41,359032
|
42,062625
|
42,776415
|
43,500402
|
44,224389
|
44,968770
|
45,713151
|
46,477926
|
47,242701
|
48,017673
|
260
|
48,813039
|
49,608405
|
50,413968
|
51,229728
|
52,055685
|
52,891839
|
53,748387
|
54,604935
|
55,471680
|
56,348622
|
270
|
57,245958
|
58,143294
|
59,050827
|
59,978754
|
60,906681
|
61,855002
|
62,81352
|
63,782235
|
64,761147
|
65,750256
|
280
|
66,749562
|
67,759065
|
68,788962
|
69,818859
|
70,869150
|
71,929638
|
73,000323
|
74,081205
|
75,182481
|
76,293954
|
290
|
77,415624
|
78,547491
|
79,689555
|
80,852013
|
82,024668
|
83,207520
|
84,410766
|
85,624209
|
86,847849
|
88,081686
|
300
|
89,335917
|
90,600345
|
91,885167
|
93,180186
|
94,485402
|
95,800815
|
97,136622
|
98,492823
|
99,849024
|
101,235816
|
310
|
102,622608
|
104,029794
|
105,457374
|
106,895151
|
108,343125
|
109,811493
|
111,300255
|
112,799214
|
114,318567
|
115,848117
|
320
|
117,387864
|
118,958202
|
120,538737
|
122,129469
|
123,740595
|
125,372115
|
127,013832
|
128,675943
|
130,358448
|
132,05115
|
330
|
133,764246
|
135,497736
|
137,241423
|
139,015701
|
140,800176
|
133,427745
|
144,420111
|
146,265768
|
148,121622
|
149,99787
|
340
|
151,894512
|
153,811548
|
155,738781
|
157,696605
|
159,674823
|
161,663238
|
163,682244
|
165,721644
|
167,771241
|
169,851429
|
350
|
171,952011
|
174,072987
|
176,214357
|
178,376121
|
180,558279
|
182,771028
|
185,004171
|
187,257708
|
189,317502
|
191,836161
|
360
|
194,171274
|
196,516584
|
198,902682
|
201,298977
|
203,73606
|
206,193537
|
208,671408
|
211,190067
|
213,72912
|
216,298764
|
370
|
218,909196
|
221,540022
|
224,211636
|
226,913841
|
229,656834
|
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-
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-
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-
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-
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